Oxazoles for treating cytokine mediated diseases

ABSTRACT

This invention relates to the novel oxazole compounds of Formula (I) and novel pharmaceutical compositions comprising a compound of Formula (I) and a pharmaceutically acceptable diluent or carrier. This invention also relates to a method of inhibiting cytokines and the treatment of cytokine mediated diseases, in mammals, thereby by administration of an effective amount of a compound according to Formula (I).

This application is a continuation of U.S. Ser. No. 08/640,966 filed May8, 1996 which is the §371 national stage entry of PCT/US94/13067, filedNov. 8, 1994 which is a continuation in part of U.S. Ser. No. 08/148,705filed Nov. 8, 1993.

FIELD OF THE INVENTION

This invention relates to a novel group of oxazole compounds, processesfor the preparation thereof, the use thereof in treating cytokinemediated diseases and pharmaceutical compositions for use in suchtherapy.

BACKGROUND OF THE INVENTION

Interleukin-1 (IL-1)and Tumor Necrosis Factor (TNF) are biologicalsubstances produced by a variety of cells, such as monocytes ormacrophages. IL-1 has been demonstrated to mediate a variety ofbiological activities thought to be important in immunoregulation andother physiological conditions such as inflammation [See, e.g.,Dinarello et al., Rev. Infect. Disease, 6, 51 (1984)]. The myriad ofknown biological activities of IL-1 include the activation of T helpercells, induction of fever, stimulation of prostaglandin or collagenaseproduction, neutrophil chemotaxis, induction of acute phase proteins andthe suppression of plasma iron levels.

There are many disease states in which excessive or unregulated IL-1production is implicated in exacerbating and/or causing the disease.These include rheumatoid arthritis, osteoarthritis, endotoxemia and/ortoxic shock syndrome, other acute or chronic inflammatory disease statessuch as the inflammatory reaction induced by endotoxin or inflammatorybowel disease; tuberculosis, atherosclerosis, muscle degeneration,cachexia, psoriatic arthritis, Reiter's syndrome, rheumatoid arthritis,gout, traumatic arthritis, rubella arthritis, and acute synovitis.Recent evidence also links IL-1 activity to diabetes and pancreatic βcells.

Dinarello, J. Clinical Immunology, 5 (5), 287-297 (1985), reviews thebiological activities which have been attributed to IL-1. It should benoted that some of these effects have been described by others asindirect effects of IL-1.

Excessive or unregulated TNF production has been implicated in mediatingor exacerbating a number of diseases including rheumatoid arthritis,rheumatoid spondylitis, osteoarthritis, gouty arthritis and otherarthritic conditions; sepsis, septic shock, endotoxic shock, gramnegative sepsis, toxic shock syndrome, adult respiratory distresssyndrome, cerebral malaria, chronic pulmonary inflammatory disease,silicosis, pulmonary sarcoisosis, bone resorption diseases, reperfusioninjury, graft vs. host reaction, allograft rejections, fever andmyalgias due to infection, such as influenza, cachexia secondary toinfection or malignancy, cachexia, secondary to acquired immunedeficiency syndrome (AIDS), AIDS, ARC (AIDS related complex), keloidformation, scar tissue formation, Crohn's disease, ulcerative colitis,or pyresis.

AIDS results from the infection of T lymphocytes with HumanImmunodeficiency Virus (HIV). At least three types or strains of HIVhave been identified, i.e., HIV-1, HIV-2 and HIV-3. As a consequence ofHIV infection, T-cell mediated immunity is impaired and infectedindividuals manifest severe opportunistic infections and/or unusualneoplasms. HIV entry into the T lymphocyte requires T lymphocyteactivation. Other viruses, such as HIV-1, HIV-2 infect T lymphocytesafter T Cell activation and such virus protein expression and/orreplication is mediated or maintained by such T cell activation. Once anactivated T lymphocyte is infected with HIV, the T lymphocyte mustcontinue to be maintained in an activated state to permit HIV geneexpression and/or HIV replication. Monokines, specifically TNF, areimplicated in activated T-cell mediated HIV protein expression and/orvirus replication by playing a role in maintaining T lymphocyteactivation. Therefore, interference with monokine activity such as byinhibition of monokine production, notably TNF, in an HIV-infectedindividual aids in limiting the maintenance of T cell activation,thereby reducing the progression of HIV infectivity to previouslyuninfected cells which results in a slowing or elimination of theprogression of immune dysfunction caused by HIV infection. Monocytes,macrophages, and related cells, such as kupffer and glial cells, havealso been implicated in maintenance of the HIV infection. These cells,like T-cells, are targets for viral replication and the level of viralreplication is dependent upon the activation state of the cells. [SeeRosenberg et al., The Immunopathogenesis of HIV Infection, Advances inImmunology, Vol. 57, (1989)]. Monokines, such as TNF, have been shown toactivate HIV replication in monocytes and/or macrophages [See Poli, etal., Proc. Natl. Acad. Sci., 87:782-784 (1990)], therefore, inhibitionof monokine production or activity aids in limiting HIV progression asstated above for T-cells.

TNF has also been implicated in various roles with other viralinfections, such as the cytomegalia virus (CMV), influenza virus, andthe herpes virus for similar reasons as those noted.

Interleukin-8 (IL-8) is a chemotactic factor first identified andcharacterized in 1987. IL-8 is produced by several cell types includingmononuclear cells, fibroblasts, endothelial cells, and keratinocytes.Its production from endothelial cells is induced by IL-1, TNF, orlipopolysachharide (LPS). Human IL-8 has been shown to act on Mouse,Guinea Pig, Rat, and Rabbit Neutrophils. Many different names have beenapplied to IL-8, such as neutrophil attractant/activation protein-1(NAP-1), monocyte derived neutrophil chemotactic factor (MDNCF),neutrophil activating factor (NAF), and T-cell lymphocyte chemotacticfactor.

IL-8 stimulates a number of functions in vitro. It has been shown tohave chemoattractant properties for neutrophils, T-lymphocytes, andbasophils. In addition it induces histamine release from basophils fromboth normal and atopic individuals as well as lysozomal enzyme releaseand respiratory burst from neutrophils. IL-8 has also been shown toincrease the surface expression of Mac-1 (CD11b/CD18) on neutrophilswithout de novo protein synthesis, this may contribute to increasedadhesion of the neutrophils to vascular endothelial cells. Many diseasesare characterized by massive neutrophil infiltration. Conditionsassociated with an increased in IL-8 production (which is responsiblefor chemotaxis of neutrophils into the inflammatory site) would benefitby compounds which are suppressive of IL-8 production.

IL-1 and TNF affect a wide variety of cells and tissues and thesecytokines as well as other leukocyte derived cytokines are important andcritical inflammatory mediators of a wide variety of disease states andconditions. The inhibition of these cytokines is of benefit incontrolling, reducing and alleviating many of these disease states.

There remains a need for treatment, in this field, for compounds whichare cytokine suppressive anti-inflammatory drugs, i.e. compounds whichare capable of inhibiting cytokines, such as IL-1, IL-6, IL-8 and TNF.

SUMMARY OF THE INVENTION

This invention relates to the novel compounds of Formula (I) andpharmaceutical compositions comprising a compound of Formula (I) and apharmaceutically acceptable diluent or carrier.

This invention also relates to a method of inhibiting cytokines and thetreatment of a cytokine mediated disease, in a mammal in need thereof,which comprises administering to said mammal an effective amount of acompound of Formula (I).

This invention more specifically relates to a method of inhibiting theproduction of IL-1 in a mammal in need thereof which comprisesadministering to said mammal an effective amount of a compound ofFormula (I).

This invention more specifically relates to a method of inhibiting theproduction of IL-8 in a mammal in need thereof which comprisesadministering to said mammal an effective amount of a compound ofFormula (I).

This invention more specifically relates to a method of inhibiting theproduction of TNF in a mammal in need thereof which comprisesadministering to said mammal an effective amount of a compound ofFormula (I).

DETAILED DESCRIPTION OF THE INVENTION

The novel compounds of this invention are represented by the structure:

wherein:

R₁ and R₂ are independently selected from an optionally substituted arylor heteroaryl group, provided that at least one of R₁ and R₂ is anoptionally substituted heteroaryl, and further provided that both R₁ andR₂ are not the same heteroaryl group;

wherein when one of R₁ and R₂ is an optionally substituted aryl ring,the ring is substituted by one or two substituents, each of which isindependently selected, and which, for a 4-phenyl, 4-naphth-1-yl or5-naphth-2-yl substituent, is halo, cyano, —C(Z)NR₇R₁₇, —C(Z)OR₂₃,—(CR₁₀R₂₀)_(m)COR₃₆, —SR₅, —SOR₅, —OR₃₆, halo-substituted-C₁₋₄ alkyl,C₁₋₄ alkyl, —ZC(Z)R₃₆, —NR₁₀C(Z)R₂₃, or —(CR₁₀R₂₀)_(m)NR₁₀R₂₀;

and which, for other positions of substitution, is halo,—(CR₁₀R₂₀)_(m″)-cyano, —C(Z)NR₁₆R₂₆, —C(Z)OR₈, —(CR₁₀R₂₀)_(m″)COR₈,—(CR₁₀R₂₀)_(m″)S(O)_(m)R₈, —(CR₁₀R₂₀)_(m″)OR₈, halo-substituted-C₁₋₄alkyl, —C₁₋₄ alkyl, —(CR₁₀R₂₀)_(m″)NR₁₀C(Z)R₈,—(CR₁₀R₂₀)_(m″)NR₁₀S(O)_(m′)R₁₁, —(CR₁₀R₂₀)_(m″)NR₁₀S(O)_(m′)NR₇R₁₇,—(CR₁₀R₂₀)_(m″)ZC(Z)R₈ or —(CR₁₀R₂₀)_(m″)NR₁₆R₂₆;

and when one of R₁ and R₂ is an optionally substituted heteroaryl group,the substituent groups include one or two substituents each of which isindependently selected from C₁₋₄ alkyl, halo, C₁₋₄ alkoxy, C₁₋₄alkylthio, NR₁₀R₂₀, or an N-heterocyclyl ring which ring has from 5 to 7members and optionally contains an additional heteroatom selected fromoxygen, sulfur or NR₂₂;

R₃ is —X_(a)P(Z)(X_(b)R₁₃)₂, X_(c) or —(CR₁₀R₂₀)_(n)R₄;

R₄ is Q—(Y₁)_(t);

Q is an aryl or heteroaryl group;

X_(c) is hydrogen, —(CR₁₀R₂₀)_(n)(Y₂)_(p),—(CR₁₀R₂₀)_(n)—C═C—(CR₁₀R₂₀)_(n)(Y₂)_(p),—(CR₁₀R₂₀)_(n)—C≡C—(CR₁₀R₂₀)_(n′)(Y₂)_(p), or halosubstituted C₁₋₁₀alkyl;

t is an integer having a value of 1 to 3;

p is 0 or an integer having a value of 1, provided that when p is 0 thenY₂ is hydrogen;

X_(a) is —NR₈—, —O—, —S— or a C₁₋₁₀ alkylene chain optionallysubstituted by C₁₋₄ alkyl and optionally interrupted by —NR₈—, —O— or—S—;

X_(b) is independently selected from —(CR₁₀R₂₀)_(n), —NR₈—, —O— or —S—;

Z is oxygen or sulfur;

n is 0 or an integer having a value of 1 to 10;

n′ is an integer having a value of 1 to 10;

m is 0, or the integer 1 or 2;

m′ is 1 or 2;

m″ is 0 or an integer having a value of 1 to 5;

Y₁ is independently selected from hydrogen, C₁₋₅ alkyl, halo-substitutedC₁₋₅ alkyl, halogen, —X_(a)—P(Z)—(X_(b)R₁₃)₂ or —(CR₁₀R₂₀)_(n)Y₂;

Y₂ is halogen, —OR₈, —NO₂, —S(O)_(m′)R₁₁, —SR₈, —S(O)_(m′)NR₈R₉, —NR₈R₉,—O(CR₁₀R₂₀)_(n′)NR₈R₉, —C(O)R₈, —CO₂R₈, —CO₂(CR₁₀R₂₀)_(n′)CONR₈R₉,—ZC(O)R₈, —CN, —C(Z)NR₈R₉, —NR₁₀C(Z)R₈, —C(Z)NR₈OR₉, —NR₁₀C(Z)NR₈R₉,—NR₁₀S(O)_(m′)R₁₁, —N(OR₂₁)C(Z)NR₈R₉, —N(OR₂₁)C(Z)R₈, —C(═NOR₂₁)R₈,—NR₁₀C(═NR₁₅)SR₁₁, —NR₁₀C(═NR₁₅)NR₈R₉, —NR₁₀C(═CR₁₄R₂₄)SR₁₁,—NR₁₀C(═CR₁₄R₂₄)NR₈R₉, —NR₁₀C(O)C(O)NR₈R₉, —NR₁₀C(O)C(O)OR₁₀,—C(═NR₁₃)NR₈R₉, —C(═NOR₁₃)NR₈R₉, —C(═NR₁₃)ZR₁₁, —OC(Z)NR₈R₉,—NR₁₀S(O)₂CF₃, —NR₁₀C(Z)OR₁₀, 5-(R₁₈)-1,2,4-oxadizaol-3-yl or4-(R₁₂)-5-(R₁₈R₁₉)-4,5-dihydro-1,2,4-oxadiazol-3-yl;

R₅ is hydrogen, C₁₋₄ alkyl, C₂₋₄ alkenyl, C₂₋₄ alkynyl or NR₇R₁₇,excluding the moieties —SR₅ being —SNR₇R₁₇ and —SOR₅ being —SOH;

R₆ is C₁₋₄ alkyl, halo-substituted-C₁₋₄ alkyl C₂₋₄ alkenyl, C₂₋₄ alkynylor C₃₋₅ cycloalkyl;

R₇ and R₁₇ is each independently selected from hydrogen or C₁₋₄ allyl orR₇ and R₁₇ together with the nitrogen to which they are attached form aheterocyclic ring of 5 to 7 members which ring optionally contains anadditional heteroatom selected from oxygen, sulfur or NR₂₂;

R₈ is hydrogen, heterocyclyl, heterocyclylalkyl or R₁₁;

R₉ is hydrogen, C₁₋₁₀ alkyl, C₂₋₁₀ alkenyl, C₂₋₁₀ alkynyl, C₃₋₇cycloalkyl, C₅₋₇ cycloalkenyl, aryl, arylalkyl, heteroaryl orheteroarylalkyl or R₈ and R₉ may together with the nitrogen to whichthey are attached form a heterocyclic ring of 5 to 7 members which ringoptionally contains an additional heteroatom selected from oxygen,sulfur or NR₁₂;

R₁₀ and R₂₀ is each independently selected from hydrogen or C₁₋₄ alkyl;

R₁₁ is C₁₋₁₀ alkyl, halo-substituted C₁₋₁₀ alkyl, C₂₋₁₀ alkenyl, C₂₋₁₀alkynyl, C₃₋₇ cycloalkyl, C₅₋₇ cycloalkenyl, aryl, arylalkyl, heteroarylor heteroarylalkyl;

R₁₂ is hydrogen, —C(Z)R₁₃ or optionally substituted C₁₋₄ alkyl,optionally substituted aryl or optionally substituted aryl-C₁₋₄ alkyl;

R₁₃ is hydrogen, C₁₋₁₀ alkyl, cycloalkyl, heterocyclyl, aryl, arylalkyl,heteroaryl or heteroarylalkyl;

R₁₄ and R₂₄ is each independently selected from hydrogen, alkyl, nitroor cyano;

R₁₅ is hydrogen, cyano, C₁₋₄ alkyl, C₃₋₇ cycloalkyl or aryl;

R₁₆ and R₂₆ is each independently selected from hydrogen or optionallysubstituted C₁₋₄ alkyl, optionally substituted aryl or optionallysubstituted aryl-C₁₋₄ alkyl, or together with the nitrogen which theyare attached form a heterocyclic ring of 5 to 7 members which ringoptionally contains an additional heteroatom selected from oxygen,sulfur or NR₁₂;

R₁₈ and R₁₉ is each independently selected from hydrogen, C₁₋₄ alkyl,substituted alkyl, optionally substituted aryl, optionally substitutedarylalkyl or together R₁₈ and R₁₉ denote a oxygen or sulfur;

R₂₁ is hydrogen, a pharmaceutically acceptable cation, C₁₋₁₀ alkyl, C₃₋₇cycloalkyl, aryl, aryl C₁₋₄ alkyl, heteroaryl, heteroarylalkyl,heterocyclyl, aroyl, or C₁₋₁₀ alkanoyl;

R₂₂ is R₁₀ or C(Z)—C₁₋₄ alkyl;

R₂₃ is C₁₋₄ alkyl, halo-substituted-C₁₋₄ alkyl, or C₃₋₅ cycloalkyl;

R₃₆ is hydrogen or R₂₃;

or a pharmaceutically acceptable salt thereof.

Suitable heteroaryl moieties for R₁ and R₂ are 4-pyridyl, pyrimidinyl,quinolyl, isoquinolinyl, 1-imidazolyl, 1-benzimidazolyl and thiophene,all of which may be optionally substituted. Preferably, the heteroarylgroup is a 4-pyridyl, 4-pyrimidinyl, 4-quinolyl, 6-isoquinolinyl,1-imidazolyl or 1-benzimidazolyl group, of which the 4-pyridyl,4-pyrimidinyl and 4-quinolyl is more preferred. Especially preferred isthe 4-pyridyl or 4-pyrimidinyl moiety, and most preferred is the4-pyrimidinyl moiety.

Suitable substituent groups for the heteroaryl moieties, R₁ and R₂,include one or two substituents each of which are independently selectedfrom C₁₋₄ alkyl, halo, C₁₋₄ alkoxy, C₁₋₄ alkylthio, NR₁₀R₂₀ or anN-heterocyclyl ring which ring has from 5 to 7 members and optionallycontains an additional heteroatom selected from oxygen, sulfur or NR₂₂.

A preferred substituent for the heteroaryl moieties is C₁₋₄ alkyl orNR₁₀R₂₀, more preferably NR₁₀R₂₀. Preferably, when the substituent isC₁₋₄ alkyl group it is methyl. When the substituent is NR₁₀R₂₀, and R₁₀and R₂₀ are a C₁₋₄ alkyl moiety, it is preferably a methyl group, andmore preferably R₁₀ and R₂₀ are not both C₁₋₄ alkyl groups. Morepreferably, both R₁₀ and R₂₀ are hydrogen or one of R₁₀ and R₂₀ arehydrogen and the other a C1-4 alkyl group, especially methyl.Preferably, the 4-pyridyl group is substituted in the 2-position and the4-pyrimidinyl group is substituted at the 2- or 4-position, morepreferably the 2-position (between the two nitrogen's of the pyrimidinering.

For the purposes herein the “core” 4-pyrimidinyl moiety is meant to bethe formula:

When the 4-pyrimidinyl moiety is substituted it is preferablysubstituted in at least one of the following positions by the moiety Y₃and Y₄ which are referred to herein in greater detail as optionalsubstituents on the heteroaryl rings R₁ and R₂:

As the nomenclature will change when either Y₃ or Y₄ is substituted, forthe purposes herein when Y₄ but not Y₃ is the substituted position it isreferred to as the 2-position. When Y₃ but not Y₄ is the substitutedposition it is referred to as the 4-position and the point of attachmentof the pyrimidinyl ring is the 6-position.

Suitable aryl groups for R₁ and R₂ include optionally substitutedphenyl, naphth-1-yl or naphth-2-yl. The aryl ring may be optionallysubstituted by one or two substituents, each of which is independentlyselected, and which, for a 4-phenyl, 4-naphth-1-yl or 5-naphth-2-ylsubstituent, is halo, cyano, —C(Z)NR₇R₁₇, —C(Z)OR₂₃,—(CR₁₀R₂₀)_(m)COR₃₆, —SR₅, —SOR₅, —OR₃₆, halo-substituted-C₁₋₄ alkyl,C₁₋₄ alkyl, —ZC(Z)R₃₆, —NR₁₀C(Z)R₂₃, or —(CR₁₀R₂₀)_(m)NR₁₀R₂₀ and which,for other positions of substitution, is halo, (CR₁₀R₂₀)_(m″)cyano,—C(Z)NR₁₆R₂₆, —C(Z)OR₈, —(CR₁₀R₂₀)_(m″)COR₈, (CR₁₀R₂₀)_(m″)S(O)_(m)R₈,(CR₁₀R₂₀)_(m″)OR₈, halo-substituted-C₁₋₄ alkyl, —C₁₋₄ alkyl,—(CR₁₀R₂₀)_(m″)NR₁₀C(Z)R₈, (CR₁₀R₂₀)_(m″)NR₁₀S(O)_(m′)R₁₁,(CR₁₀R₂₀)_(m″)NR₁₀S(O)_(m)NR₇R₁₇, (CR₁₀R₂₀)_(m″)ZC(Z)R₈ or—(CR₁₀R₂₀)_(m″)NR₁₆R₂₆;

n is 0 or an integer having a value of 1 to 10; n′ is an integer havinga value of 1 to 10; m is 0, or the integer 1 or 2; m′ is 1 or 2; and m″is 0 or an integer having a value of 1 to 5.

Preferred substitutions for R₁ or R₂ when it is a 4-phenyl,4-naphth-1-yl or 5-naphth-2-yl moiety are one or two substituents eachindependently selected from halogen, —SR₅, —SOR₅, —OR₃₆, or—(CR₁₀R₂₀)_(m)NR₁₀R₂₀, and for other positions of substitution on theserings preferred substitution is halogen, —S(O)_(m)R₈, —OR₈,—(CR₁₀R₂₀)_(m″NR) ₇R₁₇, (CR₁₀R₂₀)_(m″)NR₁₀C(Z)R₈ and—(CR₁₀R₂₀)_(m″)NR₁₀S(O)_(m′)R₁₁. More preferred substituents for the4-position in phenyl and naphth-1-yl and on the 5-position innaphth-2-yl include halogen, especially fluoro and chloro, and —SR₅ and—SOR₅ wherein R₅ is preferably a C₁₋₂ alkyl, more preferably methyl; ofwhich halogen, especially fluoro is preferred. Preferred substituentsfor the 3-position in phenyl and naphth-1-yl include: halogen,especially chloro; —OR₈, especially C₁₋₄ alkoxy; amino; —NR₁₀C(Z)R₈,especially —NHCO(C₁₋₁₀ alkyl); and —NR₁₀S(O)_(m′)R₁₁, especially—NHS(O)₂(C₁₋₁₀ alkyl).

Preferably, the aryl group is an unsubstituted or substituted phenylmoiety. More preferably, it is phenyl or phenyl substituted at the4-position with fluoro and/or substituted at the 3-position with fluoro,chloro, C₁₋₄ alloxy, methanesulfonamido or acetamido.

Preferably when one of R₁ or R₂ is the heteroaryl group, R₂ is theheteroaryl position.

Suitably, R₃ is —X_(c) or (CR₁₀R₂₀)_(n)R₄. When R₃ is —X_(c) it ispreferably hydrogen, (CR₁₀R₂₀)_(n)CH₃, or (CR₁₀R₂₀)_(n)Y₂. Morepreferably, Y₂ includes —NR₈R₉, and —NR₁₀C(Z)R₈ and n is 0 to 2. Mostpreferably, R₃ is hydrogen, methyl, amino, or acetamido.

Suitably, when R₃ is —(CR₁₀R₂₀)_(n)R₄, and Q is an aryl group, then itis preferably an optionally substituted phenyl, or if Q is a heteroarylgroup it is preferably a (un) substituted pyrrole, pyridine, orpyrimidine group. More preferably Q is phenyl or a substituted phenyl.All Q moieties are independently substituted by (Y₁)_(t), wherein t isan integer of 1 to 3. Preferably t is 1 or 2. More preferably, when R₃is monosubstituted phenyl (t=1), the substituent is located at the4-position. The n term is preferably 0 to 2.

Suitably, when R₄ is Q—(Y₁)t and when Y₁ is other than (CR₁₀R₂₀)_(n)Y₂,preferred substituents include hydrogen, halogen, or C₁₋₅ alky. When Y₁is (CR₁₀R₂₀)_(n)Y₂ and Q is mono-substituted the substituents include—(CR₁₀R₂₀)_(n)Y₂ wherein: n is 0, 1, 2 or 3, preferably 0 or 1; and Y₂is —OR₈, especially where R₈ is hydrogen or C₁₋₁₀ alkyl; —NO₂;—S(O)_(m′)R₁₁, especially where R₁₁ is C₁₋₁₀ alkyl; —SR₈, especiallywhere R₈ is C₁₋₁₀ alkyl; —S(O)_(m′)NR₈R₉, especially where R₈ and R₉ iseach hydrogen or C₁₋₁₀ alkyl or R₈ and R₉ together with the nitrogen towhich they are attached form a 5 to 7 membered ring which optionallyincludes another heteroatom selected from oxygen, sulfur or NR₁₂;—NR₈R₉, especially where R₈ and R₉ is each hydrogen, methyl or benzyl orR₈ and R₉ together with the nitrogen to which they are attached form a 5to 7 membered ring which optionally includes another heteroatom selectedfrom oxygen, sulfur or NR₁₂; —O(CR₁₀R₂₀)_(n′)NR₈R₉, especially where R₈and R₉ is each C₁₋₁₀ alkyl; —C(O)R₈, especially where R₈ is hydrogen orC₁₋₁₀ alkyl; —CO₂R₈, especially where R₈ is hydrogen or C₁₋₁₀ alkyl;—CO₂(CR₁₀R₂₀)_(n′)CONR₈R₉, especially where R₈ and R₉ is hydrogen orC₁₋₁₀ alkyl; —CN; —C(Z)NR₈R₉, especially where R₈ and R₉ is hydrogen orC₁₋₁₀ alkyl; —NR₁₀S(O)_(m′R) ₁₁, especially where R₁₀ is hydrogen orC₁₋₁₀ alkyl and R₁₁ is C₁₋₁₀ alkyl or a halosubstituted; —NR₁₀C(Z)R₈,especially where R₈ is C₁₋₁₀ alkyl and R₁₀ is hydrogen and Z is oxygen;—C(Z)NR₈OR₉, especially where R₈ and R₉ is each hydrogen and Z isoxygen; —NR₁₀C(Z)NR₈R₉, especially where R₈ and R₉ is each hydrogen orC₁₋₁₀ alkyl and Z is oxygen; —N(OR₂₁)C(Z)NR₈RR₉, especially where R₈especially where R₈, R₉ and R₂₁ is each hydrogen or C₁₋₁₀ alkyl and Z isoxygen; —C(═NOR₁₃)NR₈R₉, especially where R₈, R₉ and R₁₃ is eachhydrogen; —NR₁₀C(═NR₁₅)NR₈R₉, especially where R₈ and R₉ is hydrogen,C₁₋₁₀ alkyl or arylalkyl and R₁₅ is cyano; and5-(R₁₈)-1,2,4-oxadizaol-3-yl and4-(R₁₂)-5-(R₁₈R₁₉)-4,5-dihydro-1,2,4-oxadiazol-3-yl, especially whereR₁₂ is hydrogen and R₁₈ and R₁₉ is each hydrogen or C₁₋₁₀ alkyl ortogether are oxo.

More preferably, when Y₁ is (CR₁₀R₂₀)_(n)Y₂, n is 0 to 2 and Y₂ is —OR₈,especially where R₈ is C₁₋₁₀ alkyl; —S(O)_(m′)R₁₁, especially where R₁₁is C₁₋₁₀ alkyl; —SR₈, especially where R₈ is C₁₋₁₀ alkyl; —NR₈R₉,especially where R₈ and R₉ is hydrogen, alkyl, aryl alkyl, or aryl or R₈and R₉ together with the nitrogen to which they are attached form apyrrolidinyl, piperidinyl or morpholinyl ring, more preferably the R₈and R₉ terms in the NR₈R₉ moiety are hydrogen, methyl or benzyl; —CO₂R₈,especially where R₈ is hydrogen or C₁₋₁₀ alkyl; —S(O)_(m)NR₈R₉,especially where R₈ and R₉ is each hydrogen or C₁₋₁₀ alkyl;—NR₁₀S(O)_(m′)R₁₁, especially where R₁₀ is hydrogen and R₁₁ is C₁₋₁₀alkyl or 5-(R₁₈)-1,2,4-oxadizaol-3-yl and4-(R₁₂)-5-(R₁₈R₁₉)-4,5-dihydro-1,2,4-oxadiazol-3-yl, especially whereR₁₂ is hydrogen and R₁₈ and R₁₉ is hydrogen or C₁₋₁₀ alkyl or togetherare oxo.

Most preferably, when Y₁ is (CR₁₀R₂₀)_(n)Y₂, n is 0 to 2 and Y₂ is —OR₈,especially where R₈ is C₁₋₄; —S(O)_(m′)R₁₁, especially where R₁₁ is C₁₋₄alkyl; —SR₈, especially where R₈ is C₁₋₄ alkyl; —NR₈R₉, especially whereR₈ and R₉ is hydrogen, C₁₋₄ alkyl, phenyl C₁₋₄ alkyl, or phenyl or R₈and R₉ together with the nitrogen to which they are attached form apyrrolidinyl, piperidinyl or morpholinyl ring, more preferably the R₈and R₉ terms in the NR₈R₉ moiety are hydrogen, methyl or benzyl.Specific embodiments of mino-substituted phenyls, prefereably at the4-position, are C₁₋₁₀ alkylthio, C₁₋₁₀ alkylsulfinyl, C₁₋₁₀alkylsulfonyl, N,N-di(C₁₋₁₀ alkyl)amino C₁₋₂ alkyl, N-aralkyl-N—C₁₋₁₀alkylamino C₁₋₂ alkyl, N-morpholino C₁₋₂ alkyl C₁₋₁₀ alkylsulfonamido,sulphonamido C₁₋₂ alkyl, 5-C₁₋₁₀ alkyl-4,5-dihydro-1,2,4-oxadiazol-3-ylor 5,5-di(C₁₋₁₀ alkyl)-4,5-dihydro-1,2,4-oxadiazol-3-yl. More preferablysusbtituted with C₁₋₄ alkylthio, C₁₋₄ alkylsulfinyl, or C₁₋₄alkylsulfonyl and most preferably the C₁₋₄ alkyl is methyl.

Preferred substituents for use in R₃ when the aryl or heteroaryl group Qis disubstituted include those hereinbefore listed for use when Q ismono-substituted and, as further substituent(s), halogen and C₁₋₁₀alkyl. When Q is phenyl substituted with two or three substituents, thealkyl moieties preferably have from one to three carbons, morepreferably one. Preferred ring positions for two substituents are the 3-and 4-positions and, for three substituents, the 3-, 4- and 5-positions. The substituent at the 3- and 5-positions is preferably C₁₋₂alkyl, such as methyl, or halogen, such as bromo, fluoro or chloro,while the substituent at the 4-position is preferably hydroxyl.

In all instances herein where there is an alkenyl or alkynyl moiety as asubstituent group, such as in R₅, R₈, R₉, or R₁₁ the unsaturatedlinkage, ie., the vinylene or acetylene linkage is preferably notdirectly attached to the nitrogen, oxygen or sulfur moieties, forinstance in Y₂ as C(Z)NR₈OR₉, NR₁₀C(Z)NR₈RR₉, or OR₈.

As used herein, “optionally substituted” unless specified, refers tosuch groups as halogen, hydroxyl, alkoxy, S(O)_(m)C₁₋₆ alkyl amino, amono & di-substituted amino, such as an NR₇R₁₇ group, C₁₋₆ alkyl, halosubstituted C₁₋₆ alky, C₃₋₇ cycloalkyl, an optionally substituted arylor an optionally substituted arylalkyl wherein the substituents arehalogen, hydroxyl, alkoxy, S(O)_(m)C₁₋₆ alkyl, amino, a mono &di-substituted amino, such as an NR₇R₁₇ group, C₁₋₆ alkyl, or halosubstituted C₁₋₆ alkyl, unless otherwise specified herein.

When R₃ includes a X_(a)—P(Z)(X_(b)R₁₃)₂ group linked either directly tothe oxazole ring or indirectly via an aryl or heteroaryl group, X_(a) issuitably oxygen or C₁₋₄ alkylene, optionally interrupted by oxygen, forinstance —CH₂OCH₂— and Z and X_(b) is each oxygen, such that thepreferred groups include —OP(O)(OR₁₃)₂ and —CH₂OCH₂—P(O)(OR₁₃)₂.

In a preferred subgenus of compounds of formula (I), one of R₁ or R₂ is4-pyridyl, 2-alkyl-4pyridyl, 2-NR₁₀R₂₀-4-pyridyl, 4-pyrimidinyl,2-alkyl-pyrimidin-4yl, 2-NR₁₀R₂₀-pyrimidin-4-yl,4-NR₁₀R₂₀pyrimidin-6-yl, or 4-quinolyl. Preferably R₃ is hydrogen,methyl, amino, or acetamido or phenyl or phenyl substituted with asubstituent selected from —(CR₁₀R₂₀)_(n)Y₂ wherein n is 0, 1, 2 or 3 andY₂ is —OR₈, —NO₂, —S(O)_(m′)R₁₁, —SR₈, —S(O)_(m)NR₈R₉, —NR₈NR₉,—O(CR₁₀R₂₀)_(n)NR₈R₉, —C(O)R₈, —CO₂R₈, —CO₂R₈, —CO₂(CR₁₀R₂₀)_(n)CONR₈R₉,—CN, —C(Z)NR₈R₉, —C(Z)NR₈OR₉, —NR₁₀S(O)_(m)R₁₁, —NR₁₀C(Z)R₈,—NR₁₀C(Z)NR₈R₉, —C(═NOR₁₃)NR₈R₉, —NR₁₀C(═CR₁₄R₂₄)NR₈R₉,5(R₁₈)-1,2,4-oxadizaol-3-yl,4-(R₁₂)-5-(R₁₈R₁₉)-4,5-dihydro-1,2,4-oxadiazol-3-yl, a 3,5-dimethyl ordibromo-4-hydroxyl grouping, wherein the substiutent is preferably atthe 4-position; and the other of one of R₁ or R₂ is phenyl or phenylsubstituted by fluoro, chloro, C₁₋₄ alkoxy, S(O)_(m) C₁₋₄ alkyl,methanesulfonamido or acetamido. Preferably R₁ is the optionallysubstituted phenyl. More preferably R₃ is hydrogen, methyl, amino, oracetamido or phenyl substituted at the 4-position with C₁₋₁₀ alkyilthio,C₁₋₁₀ alkylsulfinyl, C₁₋₁₀ alkylsulfonyl.

In a more preferred subgenus R₃ is hydrogen, methyl, amino, or acetamidoor phenyl substituted at the 4-position with C₁₋₁₀ alkylthio, C₁₋₁₀alkylsulfinyl, C₁₋₁₀ alkylsulfonyl; and one of R₁ or R₂ is phenyl orphenyl substituted at the 4-position with fluoro and/or substituted atthe 3-position with fluoro; chloro, C₁₋₄ alkoxy, methane-sulfonamido oracetamido; and the other of R₁ or R₂ is 4-pyridyl, 2-alkyl-4-pyridyl,2—NR₁₀R₂₀-4-pyridyl, 4-pyrimidinyl, 2-alkyl-pyrimidin-4-yl,2-NR₁₀R₂₀-pyrimidin-4yl, 4NR₁₀R₂₀-pyrimidin-6-yl, or 4-quinolyl. Morepreferably one of R₁ or R₂ is an NR₁₀R₂₀ substituted pyrimidinyl andmost preferably it is the R₂ moiety.

Suitable pharmaceutically acceptable salts are well known to thoseskilled in the art and include basic salts of inorganic and organicacids, such as hydrochloric acid, hydrobromic acid, sulphuric acid,phosphoric acid, methane sulphonic acid, ethane sulphonic acid, aceticacid, malic acid, tartaric acid, citric acid, lactic acid, oxalic acid,succinic acid, fumaric acid, maleic acid, benzoic acid, salicylic acid,phenylacetic acid and mandelic acid. In addition, pharmaceuticallyacceptable salts of compounds of formula (I) may also be formed with apharmaceutically acceptable cation, for instance, if a substituent Y₁ inR₃ comprises a carboxy group. Suitable pharmaceutically acceptablecations are well known to those skilled in the art and include alkaline,alkaline earth, ammonium and quarternary ammonium cations.

The following terms, as used herein, refer to:

“halo”—all halogens, that is chloro, fluoro, bromo and iodo;

“C₁₋₁₀alkyl” or “alkyl”—both straight and branched chain radicals of 1to 10 carbon atoms, unless the chain length is otherwise limited,including, but not limited to, methyl, ethyl, n-propyl, iso-propyl,n-butyl, sec-butyl, iso-butyl, tert-butyl, and the like;

The term “cycloalkyl” is used herein to mean cyclic radicals, preferablyof 3 to 7 carbons, including but not limited to cyclopropyl,cyclopentyl, cyclohexyl, and the like;

The term “alkenyl” is used herein at all occurrences to mean straight orbranched chain radical of 2-10 carbon atoms, unless the chain length islimited thereto, including, but not limited to ethenyl, 1-propenyl,2-propenyl, 2-methyl-1-propenyl, 1-butenyl, 2-butenyl and the like;

“aryl”—phenyl and naphthyl;

“heteroaryl”(on its own or in any combination, such as“heteroaryloxy”)—a 5-10 membered aromatic ring system in which one ormore rings contain one or more heteroatoms selected from the groupconsisting of N, O or S, such as, but not limited, to pyrrole,thiophene, quinoline, isoquinoline, pyridine, pyrimidine, oxazole,thiazole, thiadiazole, triazole, imidazole, or benzimidazole;

“heterocyclic”(on its own or in any combination, such as“heterocyclylalkyl”)—a saturated or wholly or partially unsaturated 4-10membered ring system in which one or more rings contain one or moreheteroatoms selected from the group consisting of N, O, or S; such as,but not limited to, pyrrolidine, piperidine, piperazine, morpholine,imidazolidine or pyrazolidine;

The term “aralkyl” or “heteroarylalkyl” or “heterocyclicalkyl” is usedherein to mean C₁₋₄ alkyl as defined above unless otherwise indicated;

“aroyl”—a C(O)Ar, wherein Ar is as phenyl, napthyl, or aryl alkylderivatives, such as benzyl and the like;

“alkanoyl”—a C(O)C₁₋₁₀alkyl wherein the alkyl is as defined above;

“sulfinyl”—the oxide S(O) of the corresponding sulfide while the term“thio” refers to the sulfide.

The compounds of the-present invention may contain one or moreasymmetric carbon atoms and may exist in racemic and optically activeforms. All of these compounds are included within the scope of thepresent invention.

Exemplified compounds of formula (I) include:

5-(3-Methoxyphenyl)-2-methyl-4-(4pyridyl)oxazole;

5-(4-Fluorophenyl)-2-methyl-4-(4-pyridyl)oxazole;

4-(4-Fluorophenyl)-5-(4-pyridyl)oxazole;

4-(3-Chlorophenyl)-5-(4-pyridyl)oxazole;

2-Amino-4-(4-fluorophenyl)-5-(4-pyridyl)oxazole;

2-Dimethylamino-4-(4-fluorophenyl)-5-(4-pyridyl)oxazole;

4-(4-Fluorophenyl)-5-(4-pyrimidinyl)oxazole;

4-(4-Fluorophenyl)-5-(2-aminopyrimidin-4-yl)oxazole;

4-(4-Fluorophenyl)-5-(2-methylaminopyrimidin-4-yl)oxazole;

4-(4-Fluorophenyl)-5-(2-dimethylaminopyrimidin-4-yl)oxazole;

4-(4-Fluorophenyl)-5-(2-methylthiopyrimidin-4-yl)oxazole;

4-(3-Chlorophenyl)-5-(2-methylpyrid-4-yl)oxazole;

4-(4-Fluorophenyl)-2-methyl-5-(4-pyridyl)oxazole;

4-(4-Fluorophenyl)-2-methyl-5-(4-quinolyl)oxazole;

5-(4-Fluorophenyl)-4-(2-aminopyrimidin-4-yl)oxazole;

2-Amino-5-(4-fluorophenyl)-4-(4-pyridyl)oxazole; and

2-Dimethylamino-5-(4-fluorophenyl)-4-(4-pyridyl)oxazole.

Preferred compounds of formula (I) include:

5-(3-Methoxyphenyl)-2-methyl-4-(4-pyridyl)oxazole;

5-(4-Fluorophenyl)-2-methyl-4(4-pyridyl)oxazole;

2-Methyl-4-(Phenyl)-5-(4-pyridyl)oxazole;

4-(4-Fluorophenyl)-2-methyl-5-(4-pyridyl)oxazole;

4-(4-Fluorophenyl)-2-phenyl-5-(4-pyridyl)oxazole;

2-Amino-4-(4-fluorophenyl)-5-(4-pyridyl)oxazole.

4-(4-Fluorophenyl)-5-(4-pyridyl)oxazole;

4-(4-Fluorophenyl)-5-(2-methylpyrid-4-yl)oxazole;

4-(3,4-Dichlorophenyl)-5-(4-pyridyl)oxazole;

4-(3-Chlorophenyl)-5-(4-pyridyl)oxazole;

4-(4-Fluorophenyl)-2-(4methylthiophenyl)-5-(4-pyridyl)oxazole;.

4-(4-Fluorophenyl)-2-[4-(methylsulfinyl)phenyl]-5-(4-pyridyl)oxazole;

4-(4Fluorophenyl)-5-(2-aminopyrimidin-4-yl)oxazole; and

2-Acetamido-4-(4-fluorophenyl)-5-(4-pyridyl)oxazole.

Compounds of Formula (I) are oxazole derivatives which may be readilyprepared using procedures well known to those of skill in the art andmay be prepared by analagous methods to those indicated herein below.

Scheme I illustrates the preparation of oxazoles which are substitutedonly by a hydrogen at C-2 (R₃═H). The requisite aldehydes wherein R₂ andR₁ are defined as in formula (I) or suitably protected precursorsthereof can be prepared from readily available materials using standardtransformations known to one skilled in the art The isonitrile (I) isprepared from an aldehyde (R₂COH), formamide and a thiol or a sulfinicacid (preferably as aryl compounds) in a 3 component condensation. For amore detailed description see Example 7 herein. Reaction of I withaldehyde II is initiated with a suitable base, for example a guanidinebase such as 1,5,7 triazobicyclo[4.4.0]dec-5-ene, in an inert solventsuch as methylene chloride or DME yields oxazole III.

Scheme II illustrates the preparation of oxazoles possessing an alkylgroup at C-2 (VIII) by cyclization of an appropriate acyloxyketone VIlwith NH₄OAc/HOAc. Compound VII can be prepared as illustrated in threesteps from the desired organometalic derivative IV. A relevant exampleof the first step, preparation of ketone V, is outlined in Scheme II ofPCT/US93/00674, Adams et al., published as WO93/14081 whose disclosureis incorporated by reference herein in its entirety. Compound V can bebrominated to afford bromoketone VI. Displacement of the bromide by thesodium salt of a carboxylic acid gives acyloxyketone VII.

Scheme III illustrates an alternative route to the preparation ofoxazoles possessing an alkyl substituent at C-2 (XIII). The procedureinvolves cyclizing the appropriate acylaminoketone XI under dehydratingconditions. Three methods of preparing compound XI are shown. Two of themethods start with ketone V. In one method, compound V can be convertedto the oximinoketone IX using either acidic conditions with an aqueoussolution of an alkali nitrite salt or employing basic conditions inalcoholic solvents with an alkyl nitrite, for example, potassiumt-butoxide in t-butanol plus amyl nitrite. Subsequent reduction of theoximinoketone IX, preferably with hydrogen and a metal catalyst yieldsan aminoketone which may be prepared and isolated under acidicconditions to afford initially the hydrohalide salt which is in aseparate step acylated to produce compound XI or acylated in situ toyield directly compound XI. In the other method, the corresponding oxime(X) of V can be converted, via a Neber reaction, to an aminoketone whichafter acylation affords XI. The third method produces XI by the additionof an organomettalic derivative of R₂ to the acylated and activatedderivative of the α-amino acid of R₁.

Scheme IV illustrates the preparation of 2-aminooxazoles XV. They can beprepared from silyloxyketone XIV and the desired cyanamide using theprocedure described by Cockerill, A. F., et al, Syn., 1976, 591. Thepreparation of compound XIV is outlined in Scheme I of Adams et al.,PCT/US93/00674, supra.

The route illustrated in Scheme V allows for the preparation of2-substituted oxzaoles in which the R₃ group can be either the directattachment of a carbon (alkyl or aryl) or an oxygen or sulfur heteroatomlinker. The synthesis of the tosyl amides (XVI) and subsequentdehydration to the isonitrile (I) is analogous to that outlined inScheme I, but yields products with the sulfur leaving group at thesulfone instead of sulfide oxidation state. Either oxidation state ofsulfur is applicable to the processes outlined in Schemes I and V.Alkylation of the amide XVI on oxygen or sulfur if a thioamide is used)using an oxonium salt or under other conditions known to favorheteroatom versus carbon alkylation yields the imine XVII. Reaction ofXVII with aldehyde II under the basic conditions required to initiatecycloaddition produces the oxazole XIX. Alternatively, the isonitrile Imay be used to prepare chloroimidates (XVIII) which also undergo thebased-induced cyclization with aldehyde II. Experimental procedures forthe cyclization to the oxazole and the preparation of the intermediatesare outlined in the following articles: A. M. van Leuson et al. in Tet,Let., p143 (1976); J. Heterocyclic Chem., 18, p1127 & p1133 (1981) whosedisclosure is incorporated by reference herein in its entirety.

Once the oxazole nucleus has been established, further compounds offormula (I) may be prepared by applying standard techniques forfunctional group interconversion, for instance: —C(O)NR₈R₉ from —CO₂CH₃by heating with or without catalytic metal cyanide, e.g. NaCN, andHNR₈R₉ in CH₃OH; —OC(O)R₈ from —OH with e.g., ClC(O)R₈ in pyridine;—NR₁₀—C(S)NR₈R₉ from —NHR₁₀ with an alkylisothiocyante or thiocyanicacid; NR₆C(O)OR₆ from —NHR₆ with the alkyl chloroformate; —NR₁₀C(O)NR₈R₉from —NHR₁₀ by treatment with an isocyanate, e.g. HN═C═O or R₁₀N═C═O;—NR₁₀—C(O)R₈ from —NHR₁₀ by treatment with Cl—C(O)R₈ in pyridine;—C(═NR₁₀)NR₈R₉ from —C(NR₈R₉)SR₈ with H₃NR8⁺OAc—by heating in alcohol;—C(NR₈R₉)SR₈ from —C(S)NR₈R₉ with R₆-I in an inert solvent, e.g.acetone; —C(S)NR₈R₉ (where R₈ or R₉ is not hydrogen) from —C(S)NH₂ withHNR₈R₉, —C(═NCN)—NR₈R₉ from —C(═NR₈R₉)—SR₈ with NH₂CN by heating inanhydrous alcohol, alternatively from —C(═NH)—NR₈R₉ by treatment withBrCN and NaOEt in EtOH; —NR₁₀—C(═NCN)SR₈ from —NHR₁₀ by treatment with(R₈S)₂C═NCN; —NR₁₀SO₂R₈ from —NHR₁₀ by treatment with ClSO₂R₈ by heatingin pyridine; —NR₁₀C(S)R₈ from —NR₁₀C(O)R₈ by treatment with Lawesson'sreagent [2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide]; —NR₁₀SO₂CF₃ from —NHR₆ with triflic anhydride and base;—NR₁₀C(O)—C(O)—OR₈ from —NHR₁₀ with, e.g. methyloxalyl chloride and abase such as triethylamine; —NR₁₀C(O)—C(O)—NR₈R₉ from —NR₁₀C(O)—C(O)—OR₈with HNR₈R₉; and 1—(NR₁₀)—2-imidazolyl from —C(═NH)NHR₁₀ by heating with2-chloroacetaldehyde in chloroform (wherein R₆, R₈, R₉ and R₁₀ are ashereinbefore defined).

Suitable protecting groups for use with hydroxyl groups, for instance,are well known in the art and described in many references, forinstance, Protecting Groups in Organic Synthesis, Greene T W,Wiley-Interscience, New York, 1981 whose disclosure is incorporated byreference herein. Suitable examples of hydroxyl protecting groupsinclude silyl ethers, such as t-butyldimethyl or t-butyl-diphenyl, andalkyl ethers, such as methyl connected by an alkyl chain of variablelink, (CR₁₀R₂₀)_(n).

Pharmaceutically acid addition salts of compounds of formula (I) may beobtained in known manner, for example by treatment thereof with anappropriate amount of acid in the presence of a suitable solvent.

The invention will now be described by reference to the followingexamples which are merely illustrative and are not to be construed as alimitation of the scope of the present invention.

SYNTHETIC EXAMPLES Example 15-(3-Methoxyphenyl)-2-methyl-4-(4-pyridyl)oxazole

(a) 2-Amino-1-(3-methoxyphenyl)-2-(4-pyridyl)acetophenone hydrochloride

The title compound was prepared following the procedure of Murphy, J. G.J. Org. Chem, 1961, 26, 3104 except using2-hydroxyimino-1-(3-methoxyphenyl)-2-(4-pyridyl)acetophenone [seePCT/US93/00674, Adams et al, published as WO93/14081].

(b) 2-Acetamido-1-(3-methoxyphenyl)-2-(4-pyridyl)ethanone

To a solution of 2-amino-3-methoxy-2-(4-pyridyl)acetophenonehydrochloride (0.5 g, 1.8 mmol) in pyridine (8 mL) was added aceticanhydride (1 mL). The mixture was stirred at rt for 45 min, then pouredinto H₂O. The layers were separated and the aqueous layer was extractedwith CH₂Cl₂. The combined organic layers were washed with sat'd NaCl,then dried over MgSO₄. Evaporation of solvent gave a red oil which waspurified by flash chromatography, eluting with a solvent gradient of0-4% MeOH/CHCl₃. The title compound was isolated as a yellow oil (0.21g).

(c) 5-(3-Methoxyphenyl)-2-methyl-4-(4-pyridyl)oxazole

The title compound was prepared using the procedure of Hayes, F. N. etal., J. Amer. Chem Soc., 1955, 77, 1850 except using2-acetamido-1-(3-methoxyphenyl)-2-(4-pyridyl)ethanone: ESMS (m/z): 267(M⁺+H).

Example 2 5-(4-Fluorophenyl)-2-methyl-4-(4-pyridyl)oxazole

(a) 1-(4-Fluorophenyl)-2-(4-pyridyl)ethanone oxime

To a solution of 4-fluorophenyl-2-(4-pyridyl)acetophenone (8.08 g, 37.6mmol) [See PCT/US93/00674, Adams et al., WO93/14081] in EtOH (80 mL) wasadded hydroxylamine hydrochloride (4.12 g, 59.7 mmol) and pyridine (4.8mL, 59.7 mmol). The mixture was stirred at 60 ° C. for 1 h, then pouredinto H₂O and stirred an additional 1 min. The resulting precipitate wasfiltered and washed with H₂O. The precipitate was recrystallized fromEtOH/H₂O to give the title compound as a white solid (6.29 g): mp135-136° C.

(b) 2-Acetamido-1-(4-fluorophenyl)-2-(4-pyridyl)ethanone

The title compound was prepared by the procedure of Shilcrat, S. C. etal., J. Heterocyclic Chem, 1991, 28, 1181 except using1-(4-fluorophenyl)-2-(4-pyridyl)ethanone oxime and acetic anhydride.

(c) 5-(4-Fluorophenyl)-2-methyl-4-(4-pyridyl)oxazole

The title compound was prepared using the procedure of Hayes, F. N. etal, J. Amer. Chem. Soc., 1955, 77, 1850 except using2-acetamido-1-(4-fluorophenyl)-2-(4-pyridyl)ethanone: ESMS (m/z): 255(M⁺+H).

Example 3 2-Methyl-4-phenyl-5-(4-pyridyl)oxazole

(a) 2-Phenyl-1-(4-pyridyl)acetophenone

A suspension of isonicotinoyl chloride (0.58 g, 3.26 mmol) in dry THF(7.0 mL) was cooled to −78° C., and benzyl magnesium chloride (3.4 mL,6.85 mmol; 2.0 M soln in THF) was added dropwise. After the addition wascomplete, the ice bath was removed and the reaction mixture was allowedto warm to room temperature. After 3 h the reaction mixture was pouredinto saturated NH₄Cl and the layers were separated. The aqueous mixturewas extracted with THF. The combined organic layers were washed withsat'd NaCl and dried over MgSO₄. Evaporation of solvent gave a yellowsolid which was purified by flash chromatography, eluting with a solventgradient of 0-3% MeOH/CH₂Cl₂. The title compound was isolated as ayellow solid (0.50 g).

(b) 1-Hydroxyimino-1-phenyl-1-(4-pyridyl) ethanone

To a solution of 2-phenyl-1-(4-pyridyl)acetophenone (0.50 g, 2.53 mmol)in pyridine (7.5 mL) was added hydroxylamine hydrochloride (0.65 g, 9.36mmol). After stirring at rt for 20 h, the pyridine was evaporated andthe residue was taken up in H₂O and filtered. The precipitate was washedwith H₂O and air-dried giving the title compound as a yellow solid(0.529 g).

(c) 2-Acetamido2-(4-phenyl)-1-(4-pyridyl)ethanone

Sodium (0.08 g, 3.50 mmol) was added to absolute EtOH (16 mL) andstirred. Upon completion of the reaction and cooling to ambienttemperature, 1-Hydroxyimino-2-phenyl-1-(4-pyridyl)ethanone (0.53 g, 2.50mmol) was added portionwise. After 15 min, the yellow reaction mixturewas cooled in an ice-bath and p-toluenesulfonyl chloride (0.59 g, 3.07mmol) was added in a single portion. The mixture was stirred at −5° C.for 2 h and then a solution of NaOEt [from sodium (0.07 g, 5.18 mmol)and absolute EtOH (3.3 mL)] was added dropwise. After 45 min, Et₂O (9mL) was added and the stirring was continued. After 30 min, the solventwas evaporated and the residue was partitioned between Et₂O and 3N HCl.The layers were separtated and the Et₂O layer was extracted with HCl.The aqueous phase was evaporated to give a yellow oil (1.52 g) which wasdissolved in pyridine (10 mL). Acetic anhydride (1 mL) was added and thereaction mixture was stirred at rt. After 19 h, the mixture was pouredinto H₂O and CH₂Cl₂ was added. The layers were separated and the aqueouslayer was extracted with CH₂Cl₂. The combined organic layers were washedwith sat'd NaCl and dried over MgSO₄. Evaporation of solvent gave a redoil which was purified by flash chromatography, eluting with 0-3%MeOH/CHCl₃. The title compound was obtained as a gold oil (0.238 g).

(d) 2-Methyl-4-phenyl-5-(4-pyridyl)oxazole

A mixture of 2-acetamido-2-phenyl-1-(4-pyridyl)ethanone (0.101 g, 0.397mmol) in conc. H₂SO₄ (1 mL) was heated at 100° C. for 18 h. Aftercooling, the mixture was poured onto ice and neutralized with 2.5N NaOH.The aqueous mixture was extracted with CH₂Cl₂ and the combined organicextracts were washed with sat'd NaCl and dried over MgSO₄. Evaporationof solvent gave an oil which was purified by flash chromatography,eluting with 0-2% MeOH/CHCl₃. The title compound was obtained as a goldoil (3.0 mg): MS(DCI/NH₃) (m/z): 237 (M⁺+H).

Example 4 4-(4-Fluorophenyl)-2-methyl-5-(4-pyridyl)oxazole

To a solution of 4-fluorophenyl-2-(4-pyridyl)acetophenone [SeePCT/US93/00674, Adams et al., published as WO93/14081](0.167 g, 0.76mmol) in CH₂Cl₂ (5 mL) was added bromine (7.8 mL, 0.78 mmol; 0.1M solnin CH₂Cl₂). After stirring at room temperature for 30 min, the solventwas removed in vacuo and the solid was taken up in glacial acetic acid(10 mL). Sodium acetate (0.192 g, 2.34 mmol) and ammonium acetate (0.301g, 3.9 mmol) were added and the reaction mixture was heated at refluxfor 19 h. After cooling, the mixture was poured into H₂O, neutralizedwith conc. NH₄OH, then extracted exhaustively with CH₂Cl₂. The combinedorganic layers were washed with sat'd NaCl and dried over MgSO₄.Evaporation of solvent provided a yellow solid which was purified byflash chromatography, eluting with 100% CHCl₃. The title compound wasobtained as a yellow waxy solid (0.067 g): ESMS (m/z): 255 (M⁺+H).

Example 5 4-(4-Fluorophenyl)-2-phenyl-5-(4-pyridyl)oxazole

(a) 2-Benzoyloxy-1-(4-fluorophenyl)-2-(4-pyridyl)ethanone

To a solution of 4 -fluorophenyl-2-(4-pyridyl)acetophenone [SeePCT/US93/00674, Adams et al., published as WO93/14081 (0.356 g, 1.65mmol) in CH₂Cl₂ (5 mL) was added bromine (18.1 mL, 1.81 mmol; 0.1M solnin CH₂Cl₂). After stirring at rt for 30 min, the solvent was removed invacuo and the solid was taken up in EtOH (5 mL). Sodium benzoate (0.635g, 4.4 mmol) and conc. H₂SO₄ (3 drops) were added and the mixture washeated at reflux for 18 h. After cooling, the mixture was poured intoH₂O, neutralized with conc. NH₄OH, then extracted with EtOAc. Thecombined organic extracts were washed with sat'd NaCl and dried overMgSO₄ . Evaporation of solvent gave a red oil which was filtered througha pad of silica gel, eluting with a solvent gradient of 100:0 to 50:1CHCl₃/MeOH. The title compound was isolated as a yellow oil (0.131 g).

(b) 4-(4-Fluorophenyl)-2-phenyl-5-(4-pyridyl)oxazole

A solution of 2-benzoyloxy-1-(4-fluorophenyl)-2-(4-pyridyl)ethanone(0.131 g, 0.391 mmol) and ammonium acetate (0.28 g, 3.63 mmol) inglacial acetic acid (3 mL) was heated at reflux for 1.5 h. Aftercooling, the mixture was neutralized with conc. NH₄OH and the solventwas removed in vacuo to give a yellow oil. Purification by flashchromatography (15-25% EtOAc/Hex) afforded the title compound as a whitesolid (9.0 mg): ESMS (m/z): 317 (M⁺+H).

Example 6 2-Amino-4-(4-fluorophenyl)-5-(4-pyridyl)oxazole

A mixture of1-(t-butyldimethylsilyloxy)-2-(4-fluorophenyl)-1-(4-pyridyl)ethanone[See Ex. 79 (a) of Adams et al., WO93/14081] (5.16 g, 15.0 mmol),cyanamide (0.95 g, 22.5 mmol) and KOH (0.55 g, 9.8 mmol) in EtOH (20 mL)was heated at reflux for 1 h. After cooling, the precipitate wasfiltered and washed with EtOH. Recrystallization from CH₂Cl₂/MeOHafforded the title compound as a yellow solid (0.38 g): ESMS (m/z): 256(M⁺+H).

Example 7 4-(4-Fluorophenyl)-5-(4-pyridyl)oxazole

a) 4′-fluorophenyl-(tolylthio)methylformamide

A soln of p-Fluorobenzaldehyde (13.1 mL, 122 mmol) thiocresol (16.64 g,122 mmol), formamide (15.0 mL, 445 mmol), and toluene (300 mL) werecombined and heated to toluene reflux with azeotropic removal of H₂O for18 h. The cooled reaction was diluted with EtOAc (500 mL) and washedwith satd aq Na₂CO₃(3×100 mL), satd aq NaCl (100 mL), dried (Na₂SO₄),and concentrated. The residue was triturated with petroleum ether,filtered and dried in vacuo to afford 28.50 g of the title compound as awhite solid (85%). mp=119-120°.

b) 4′-fluorophenyl-(tolylthio)methylisocyanide

4′-Fluorophenyl-(tolylthio)methlylformamide (25 g, 91 mmol) in CH₂Cl₂(300 mL) was cooled to −30 ° and, with mechanical stirring, POCl₃ (11mL, 110 mmol) was added dropwise followed by the dropwise addition ofEt₃N (45 mL, 320 mmol) with the temperature maintained below −30°.Stirred at −30° for 30 min and 5° for 2 h, diluted with CH₂Cl₂ (300 mL)and washed with 5% aq Na₂CO₃ (3×100 mL), dried (Na₂SO₄) and concentratedto 500 mL. This soln was filtered through a 12×16 cm cylinder of silicain a large sintered glass funnel with CH₂Cl₂ to afford 12.5 g (53%) ofpurified isonitrile as a light brown, waxy solid. IR (CH₂Cl₂) 2130 cm⁻¹.

c) 4-(4-Fluorophenyl)-5-(4-pyridyl)oxazole

4-Flourophenyl-(tolylthio)methylisocyanide (2.57 g, 10 mmol), pyridine-4-carboxaldehyde (1.07 g, 10 mmol) and CH₂Cl₂ (20 mL) were stirred underAr at −15° (ice-methanol bath) and TBD (1.39 g, 10 mmol) was addedportionwise. The reaction temperature rose to 5° before recooling to−15°. The reaction was allowed to warm to 4° and was kept at thattemperature for 18 h, diluted with EtOAc (100 mL) and washed with 10% aqNa₂CO₃ (3×25 ml). The EtOAc was then extracted with 1 N HCl (3×15 mL)and crystals formed from the aqueous phase. After standing for 1 h at23° the crystals were filtered off, washed with abs EtOH (25 ml) andEt₂O (2×25 mL) and dried in vacuo to afford 1.47 g (53%) of the titlecmpd as the hydrochloride. The aq filtrate was washed with EtOAC (2×40mL) and made basic by the careful addition of solid K₂CO₃. Extraction ofwith EtOAc (3×40 ml) drying (Na₂SO₄) concentration and crystallizationof the residue (hexane/acetone) afforded an additional 0.426 g (18%) ofthe title compound as the free base, mp (free base)=110-111°.

Example 8 4-(4-Fluorophenyl)-5-(2-methylpyrid-4-yl)oxazole

The compound of example 7(b) (0.599 g, 2.33 mmol) and 2-methylpyridine4-carboxaldehyde (257 mg, 2.12 mmol) and CH₂Cl₂ (4 ml) were reacted bythe procedure of Example 7. The resulting reaction was worked up bydilution with EtOAc (40 mL), washing with satd aq Na₂CO₃ (2×15 mL),extraction of the EtOAc with 1N HCl (3×15 mL). The combined aq phaseswere washed with EtOAc (3×25 mL) and then made basic by the carefuladdition of K₂CO₃. Extraction of the aq with EtOAc (4×40 mL), drying(Na₂SO₄) and concentration afforded a tan oil which could not be made tosolidify. The residue was dissolved in 9:1 Et₂O/acetone (20 mL) and 1 Netherial HCl (3 mL) was added. The precipitated solid was washed withEt₂O and dried in vacuo to afford 471 mg (79%) of the title compound asthe hydrochloride, mp=198-200 (dec).

Example 9 4-(3,4-Dichlorophenyl)-5-(4-pyridyl)oxazole

Using the method of example 7 (a,b,c) substituting3,4,-dichlorobenzaldehyde for 4-fluorobenzalderyde the title compoundwas prepared. mp=142°.

Example 10 4-(3-Chlorophenyl)-5-(4-pyridyl)oxazole

Using the method of example 7 (a,b,c) substituting 3-chlorobenzaldehydefor 4-fluorobenzaldehyde the titile compound was prepared. mp=125-126°.

Example 114-(4-Fluorophenyl)-2-(4-methylthiophenyl)-5-(4-pyridyl)oxazole

(a) 2-(4-Fluorophenyl)-1-(4-pyridyl)-2-oxoethyl 4-methylthiobezoate and1-(4-Fluorophenyl)-2-(4-pyridyl)-2-oxoethyl 4-methylthiobenzoate

The title compounds were prepared using the same procedure of Lantos etal. (J. Med. Chem. 1984, 27, 72) whose disclosure is incorporated byreference herein, and used to prepare 1-(4-fluorophenyl)-2-(4-pyridyl)-2-oxoethyl benzoate and2-(4-fluorophenyl)-1-(4-pyridyl)-2-oxoethyl benzoate, except using1-cyano-1-(4-pyridyl)methyl 4-methylthiobenzoate.

(b) 4-(4-Fluorophenyl)-2-(4-methylthiophenyl)-5-(4-pyridyl)oxazole

To a solution containing a mixture of2-(4-fluorophenyl)-1-(4-pyridyl)-2-oxoethyl 4-methylthiobenzoate and1-(4-fluorophenyl)-2-(4-pyridyl)-2-oxoethyl 4 methylthiobenzoate (1.0 g,2.62 mmol) in glacial acetic acid (50 mL) was added ammonium acetate(2.0 g, 26.2 mmol). The resulting mixture was heated at reflux for 1.5h, then allowed to cool. The mixture was poured into H₂O, neutralizedwith conc. NH₄OH and extracted with CH₂Cl₂. The combined organicextracts were washed with sat'd NaCl and dried over MgSO₄. Purificationby column chromatography, eluting with 5:1 to 1:1 Hex/EtOAc afforded thetitle compound (77.6 mg) as a yellow solid: ESMS (m/z): 363.0 (M⁺+H).

Example 124-(4-Fluorophenyl)-2-[4-(methylsulfinyl)phenyl]-5-(4-pyridyl)oxazole

To a mixture of4-(4-fluorophenyl)-2-(4methylthiophenyl)-5-(4-pyridyl)oxazole (0.056 g,0.15 mmol) in glacial acetic acid (12 mL) was added a solution of K₂S₂O₈(0.07 g, 024 mmol) in H₂O (2 mL). After stirring at rt for 48 hr, theprecipitate was filtered. Purification by column chromatography (25:1CH₂Cl₂/MeOH), followed by trituration with Et₂O afforded the titlecompound (0.014 g) as a white solid: ESMS (m/z)=379.0 (M⁺+H).

Example 13 2-Acetamido-4-(4-fluorophenyl)-5-(4-pyridyl)oxazole

A mixture of 2-amino-4-(4-fluorophenyl)-5-(4-pyridyl)oxazole (0.090 g,0.353 mmol) in acetic anhydride (4 mL) was stirred at room temperature.After 72 h the mixture was poured into H₂O and neutralized with conc.NH₄OH. The resulting precipitate was filtered and washed with H₂O.Purification by column chromatography (0-5% MeOH/CHCl₃), followed byrecrystallization from MeOH afforded the title compound as a white solid(30.0 mg):ESMS (m/z): 298.0 (M⁺+H).

Example 14 4-(4-Fluorophenyl)-5-(2-amino4-pyrimidinyl)oxazole

a) 1-N,N-dimethylamino-(4,4-dimethoxy)buten-3-one

Pyruvic aldehyde dimethyl acetal (50 ml, 0.4106 mol) andN,N-Dimethylformamide dimethyl acetal (54.5 ml,0.4106 mol) were mixedneat and heated to 80 ° C. for eighteen hours. Crude product (95.0 g)was used without further purification.

b) 2Amino-4(dimethoxymethyl)pyrimidine

Guanidine HCl (43 g) was mixed in water (150 ml) and added to1-N,N-dimethylamino-(4,4-dimethoxy)buten-3-one (95.0 g,crude) at roomtemperature. Sodium hyroxide was mixed in water and added to reactionmixture at room temperature. The reaction was then heated to 60° C. foreighteeen hours. A percipitate formed and was filtered and washed withwater. The crude product (32.5 g) was used without further purification.

c) 2-Amino-(pyrimidinyl)aldehyde

2-Amino-4-(dimethoxymethyl)pyrimidine( 6.6g, 0.0390 mol) was mixed in 3NHCl (29.96 ml, 0.0858) neat and heated to 47° C. for sixteen hours. Thereaction was cooled to room temperature and ethyl acetate (150 ml) wasadded. NaHCO₃ (16.17 g, 0.1716 mol) was then added slowly. The mixturewas stirred and the organic layer decanted, this was repeated a total offive times. The organic phases were combined and evaporated to yield theproduct—a yellow solid (2.33g, 48%). ¹H NMR (400 MHz,CDCl₃) δ9.80 (s,1H), 8.50 (d, 1H), 7.08 (d, 1H) 5.25 (s broad, 2H).

d) 2-Aminopyrimidine-[2,2,6,6-tetramethylpiperidinyl]imine

2-Amino-(pyrimidin-4-yl)aldehyde (2.33 g, 0.0189 mol) and4-Amino-(2,2,6,6-tetramethyl)piperidine (3.24 ml, 0.0189) were mixed inCH₂Cl₂ at room temperature for eight hours to yield the crude product(which contains the imine plus a large, approx. equal amount ofunreacted 2-amino-(pyrimidin-4-yl)aldehyde) (4.92 g) which was usedwithout further purification. ¹H NMR (400 MHz, CDCl₃) δ8.38 (d, 1H),8.20 (s, 1H), 7.25 (d, 1H), 5.10 (s broad, 2H), 1.79 (m, 1H) 1.70 ( m,1H), 1.40(t, 2H), 1.30-1.00 (m, 12H),0.85 ( t, 2H).

e) 4-(4-Fluorophenyl)-5-(2-amino-4-pyrimidinyl)oxazole

The crude mixture from step (d) above (4.92 g) was mixed in CH₂Cl₂ andcooled to 0° C. 4′-Fluorophenyl(tolylthio)methylisocyanide (4.86 g,0.0189 mol—refer to Example 7 a) and 7 b) above) and1.5.7.triazabicyclo[4.4.0.]dec-5-ene (2.63 g, 0.0189 mol) were mixed inCH₂Cl₂ and added dropwise to the cold reaction mixture. The reaction waskept cold for forty-eight hours. The solvent was evaporated and thecrude mixture purified by flash chromatography (silica gel,CH₂Cl₂/methanol) to yield two products; an imidazole derivative[4-(4-Fluorophenyl)-5-(2-amino-4-pyrimidinyl)-pyrazole] and the titlecompound (550 mg). ¹H NMR δ8.36 ( d,1H), 8.05 (s,1H), 7.95 (m, 2H), 7.15(m, 2H), 6.95 (d, 1H), 5.10 (s broad, 2H),

Methods of Treatment

The compounds of Formula (I) or a pharmaceutically acceptable saltthereof can be used in the manufacture of a medicament for theprophylactic or therapeutic treatment of any disease state in a human,or other mammal, which is excacerbated or caused by excessive orunregulated cytokine production by such mammal's cell, such as, but notlimited to monocytes and/or macrophages.

Compounds of formula (I) are capable of inhibiting proinflammatorycytokines, such as IL-1, IL6, IL8 and TNF and are therefore of use intherapy. IL-1, IL-8 and TNF affect a wide variety of cells and tissuesand these cytokines, as well as other leukocyte-derived cytokines, areimportant and critical inflammatory mediators of a wide variety ofdisease states and conditions. The inhibition of these pro-inflammatorycytokines is of benefit in controlling, reducing and alleviating many ofthese disease states.

Accordingly, the present invention provides a method of treating acytokine-mediated disease which comprises administering an effectivecytokine-interfering amount of a compound of formula (I) or apharmaceutically acceptable salt thereof.

In a specific embodiment the present invention provides for a method oftreating inflammation in a mammal which method comprises administeringan effective amount of a compound of formula (I) or a pharmaceuticallyacceptable salt thereof. Another specific embodiment of the presentinvention provides for a method of treating stroke, asthma, ARDS,ischemia, and/or arthritis in a mammal which method comprisesadministering an effective amount of a compound of formula (I) or apharmaceutically acceptable salt thereof.

In particular, compounds of formula (I) or a pharmaceutically acceptablesalt thereof are of use in the prophylaxis or therapy of any diseasestate in a human, or other mammal, which is exacerbated by or caused byexcessive or unregulated IL-1, IL-8 or TNF production by such mammal'scell, such as, but not limited to, monocytes and/or macrophages.

Accordingly, in another aspect, this invention relates to a method ofinhibiting the production of IL-1 in a mammal in need thereof whichcomprises administering to said mammal an effective amount of a compoundof formula (I) or a pharmaceutically acceptable salt thereof.

There are many disease states in which excessive or unregulated IL-1production is implicated in exacerbating and/or causing the disease.These include arthritis, rheumatoid arthritis, osteoarthritis,endotoxemia and/or toxic shock syndrome, other acute or chronicinflammatory disease states such as the inflammatory reaction induced byendotoxin or inflammatory bowel disease, tuberculosis, atherosclerosis,muscle degeneration, multiple sclerosis, cachexia, bone resorption,psoriatic arthritis, Reiter's syndrome, rheumatoid arthritis, gout,traumatic arthritis, rubella arthritis and acute synovitis. Recentevidence also links IL-1 activity to diabetes, pancreatic β cells andAlzheimer's disease.

In a further aspect, this invention relates to a method of inhibitingthe production of TNF in a mammal in need thereof which comprisesadministering to said mammal an effective amount of a compound offormula (I) or a pharmaceutically acceptable salt thereof.

Excessive or unregulated TNF production has been implicated in mediatingor exacerbating a number of diseases including rheumatoid arthritis,rheumatoid spondylitis, osteoarthritis, gouty arthritis and otherarthritic conditions, sepsis, septic shock, endotoxic shock, gramnegative sepsis, toxic shock syndrome, adult respiratory distresssyndrome, cerebral malaria, chronic pulmonary inflammatory disease,silicosis, pulmonary sarcoisosis, bone resorption diseases, such asosteoporosis, reperfusion injury, stroke, graft vs. host reaction,allograft rejections, fever and myalgias due to infection, such asinfluenza, cachexia secondary to infection or malignancy, cachexiasecondary to acquired immune deficiency syndrome (AIDS), AIDS, ARC (AIDSrelated complex), keloid formation, scar tissue formation, Crohn'sdisease, ulcerative colitis and pyresis.

Compounds of formula (I) are also useful in the treatment of viralinfections, where such viruses are sensitive to upregulation by TNF orwill elicit TNF production in vivo. The viruses contemplated fortreatment herein are those that produce TNF as a result of infection, orthose which are sensitive to inhibition, such as by decreasedreplication, directly or indirectly, by the TNF inhibiting-compounds offormula (I). Such viruses include, but are not limited to HIV-1, HIV-2and HIV-3, Cytomegalovirus (CMV), Influenza, adenovirus and the Herpesgroup of viruses, such as but not limited to, Herpes Zoster and HerpesSimplex. Accordingly, in a further aspect, this invention relates to amethod of treating a mammal, preferably a human, afflicted with a humanimmunodeficiency virus (HIV) which comprises administering to suchmammal an effective TNF inhibiting amount of a compound of formula (I)or a pharmaceutically acceptable salt thereof.

Compounds of formula (I) may also be used in association with theveterinary treatment of mammals, other than in humans, in need ofinhibition of TNF production.

TNF mediated diseases for treatment, therapeutically orprophylactically, in animals include disease states such as those notedabove, but in particular viral infections. Examples of such virusesinclude, but are not limited to, the lentivirus infections such asequine infectious anaemia virus, caprine arthritis virus, visna virus,or the maedi virus, or the retroviruses, such as feline immunodeficiencyvirus (FIV), bovine immunodeficiency virus, or canine immunodeficiencyvirus.

The compounds of formula (I) may also be used topically in the treatmentor prophylaxis of topical disease states mediated by or exacerbated byexcessive cytokine production, such as by IL-1 or TNF respectively, suchas inflamed joints, eczema, psoriasis and other inflammatory skinconditions such as sunburn; inflammatory eye conditions includingconjunctivitis; pyresis, pain and other conditions associated withinflammation.

Compounds of formula (I) have also been shown to inhibit the productionof IL-8 (Interleukin-8, NAP). Accordingly, in a further aspect, thisinvention relates to a method of inhibiting the production of IL-8 in amammal in need thereof which comprises administering to said mammal aneffective amount of a compound of formula (I) or a pharmaceuticallyacceptable salt thereof.

There are many disease states m which excessive or unregulated IL-8production is implicated in exacerbating and/or causing the disease.These diseases are characterized by massive neutrophil infiltration suchas, psoriasis, inflammatory bowel disease, asthma, cardiac and renalreperfusion injury, adult respiratory distress syndrome, thrombosis andglomerulonephritis. All of these diseases are associated with increasedIL-8 production which is responsible for the chemotaxis of neutrophilsinto the inflammatory site. In contrast to other inflammatory cytokines(IL-1, TNF, and IL-6), IL-8 has the unique property of promotingneutrophil chemotaxis and activation. Therefore, the inhibition of IL-8production would lead to-a direct reduction in the neutophilinfiltration.

The compounds of formula (I) are administered in an amount sufficient toinhibit cytokine, in particular IL-1, IL-8 or TNF, production such thatit is regulated down to normal levels, or in some case to subnormallevels, so as to ameliorate or prevent the disease state. Abnormallevels of IL-1, IL-8 or TNF, for instance in the context of the presentinvention, constitute: (i) levels of free (not cell bound) IL-1, IL-8 orTNF greater than or equal to 1 picogram per ml; (ii) any cell associatedIL-1, IL-8 or TNF; or (iii) the presence of IL-1, IL-8 or TNF mRNA abovebasal levels in cells or tissues in which IL-1, IL-8 or TNF,respectively, is produced.

The discovery that the compounds of formula (I) are inhibitors ofcytokines, specifically IL-1, IL-8 and TNF is based upon the effects ofthe compounds of formulas (I) on the production of the IL-1, IL-8 andTNF in in vitro assays which are described herein.

As used herein, the term “inhibiting the production of IL-1 (IL-8 orTNF)” refers to:

a) a decrease of excessive in vivo levels of the cytokine (IL-1, IL-8 orTNF) in a human to normal or sub-normal levels by inhibition of the invivo release of the cytokine by all cells, including but not limited tomonocytes or macrophages;

b) a down regulation, at the genomic level, of excessive in vivo levelsof the cytokine (IL-1, IL-8 or TFN) in a human to normal or sub-normallevels;

c) a down regulation, by inhibition of the direct synthesis of thecytokine (IL-1, IL-8 or TNF) as a postranslational event; or

d) a down regulation, at the translational level, of excessive in vivolevels of the cytokine (IL-1, IL8 or TNF) in a human to normal orsub-normal levels.

As used herein, the term “TNF mediated disease or disease state” refersto any and all disease states in which TNF plays a role, either byproduction of TNF itself, or by TNF causing another monokine to bereleased, such as but not limited to IL-1, IL-6 or IL-8. A disease statein which, for instance, IL-1 is a major component, and whose productionor action, is exacerbated or secreted in response to TNF, wouldtherefore be considered a disease stated mediated by TNF.

As used herein, the term “cytokine” refers to any secreted polypeptidethat affects the functions of cells and is a molecule which modulatesinteractions between cells in the immune, inflammatory or hematopoieticresponse. A cytokine includes, but is not limited to, monokines andlymphokines, regardless of which cells produce them. For instance, amonokine is generally referred to as being produced and secreted by amononuclear cell such as a macrophage and/or monocyte. Many other cellshowever also produce monokines, such as natural killer cells,fibroblasts, basophils, neutrophils, endothelial cells, brainastrocytes, bone marrow stromal cells, epideral keratinocytes andB-lymphocytes. Lymphokines are generally referred to as being producedby lymphoctye cells. Examples of cytokines include, but are not limitedto, Interleukin-1 (IL-1), Interleukin-6 (IL6), Interleukin-8 (IL8),Tumor Necrosis Factor-alpha (TNF-α) and Tumor Necrosis Factor. beta(TNF-β).

As used herein, the term “cytokine interfering” or “cytokine suppressiveamount” refers to an effective amount of a compound of formula (I) whichwill cause a decrease in the in vivo levels of the cytokine to normal orsubnormal levels, when given to a patient for the prophylaxis ortreatment of a disease state which is exacerbated by, or caused by,excessive or unregulated cytokine production.

As used herein, the cytokine referred to in the phrase “inhibition of acytokine, for use in the treatment of a HIV-infected human” is acytokine which is implicated in (a) the initiation and/or maintenance ofT cell activation and/or activated T cell-mediated HIV gene expressionand/or replication and/or (b) any cytokine-mediated disease associatedproblem such as cachexia or muscle degeneration.

As TNF-β (also known as lymphotoxin) has close structural homology withTNF-α (also known as cachectin) and since each induces similar biologicresponses and binds to the same cellular receptor, both TNF-α and TNF-βare inhibited by the compounds of the present invention and thus areherein referred to collectively as “TNF” unless specifically delineatedotherwise.

In order to use a compound of formula (I) or a pharmaceuticallyacceptable salt thereof in therapy, it will normally be formulated intoa pharmaceutical composition in accordance with standard pharmaceuticalpractice. This invention, therefore, also relates to a pharmaceuticalcomposition comprising an effective, non-toxic amount of a compound offormula (I) and a pharmaceutically acceptable carrier or diluent.

Compounds of formula (I), pharmaceutically acceptable salts thereof andpharmaceutical compositions incorporating such may conveniently beadministered by any of the routes conventionally used for drugadministration, for instance, orally, topically, parenterally or byinhalation. The compounds of formula (I) may be administered inconventional dosage forms prepared by combining a compound of formula(I) with standard pharmaceutical carriers according to conventionalprocedures. The compounds of formula (I) may also be administered inconventional dosages in combination with a known, second therapeuticallyactive compound. These procedures may involve mixing, granulating andcompressing or dissolving the ingredients as appropriate to the desiredpreparation. It will be appreciated that the form and character of thepharmaceutically acceptable character or diluent is dictated by theamount of active ingredient with which it is to be combined, the routeof administration and other well-known variables. The carrier(s) must be“acceptable” in the sense of being compatible with the other ingredientsof the formulation and not deleterious to the recipient thereof.

The pharmaceutical carrier employed may be, for example, either a solidor liquid. Exemplary of solid carriers are lactose, terra alba, sucrose,talc, gelatin, agar, pectin, acacia, magnesium stearate, stearic acidand the like. Exemplary of liquid carriers are syrup, peanut oil, oliveoil, water and the like. Similarly, the carrier or diluent may includetime delay material well known to the art, such as glycerylmono-stearate or glyceryl distearate alone or with a wax.

A wide variety of pharmaceutical forms can be employed. Thus, if a solidcarrier is used, the preparation can be tableted, placed in a hardgelatin capsule in powder or pellet form or in the form of a troche orlozenge. The amount of solid carrier will vary widely but preferablywill be from about 25 mg. to about 1 g. When a liquid carrier is used,the preparation will be in the form of a syrup, emulsion, soft gelatincapsule, sterile injectable liquid such as an ampule or nonaqueousliquid suspension.

Compounds of formula (I) may be administered topically, that is bynon-systemic administration. This includes the application of a compoundof formula (I) externally to the epidermis or the buccal cavity and theinstillation of such a compound into the ear, eye and nose, such thatthe compound does not significantly enter the blood stream. In contrast,systemic administration refers to oral, intravenous, intraperitoneal andintramuscular administration.

Formulations suitable for topical administration include liquid orsemi-liquid preparations suitable for penetration through the skin tothe site of inflammation such as liniments, lotions, creams, ointmentsor pastes, and drops suitable for administration to the eye, ear ornose. The active ingredient may comprise, for topical administration,from 0.001% to 10% w/w, for instance from 1% to 2% by weight of theformulation. It may however comprise as much as 10% w/w but preferablywill comprise less than 5% w/w, more preferably from 0.1% to 1% w/w ofthe formulation.

Lotions according to the present invention include those suitable forapplication to the skin or eye. An eye lotion may comprise a sterileaqueous solution optionally containing a bactericide and may be preparedby methods similar to those for the preparation of drops. Lotions orliniments for application to the skin may also include an agent tohasten drying and to cool the skin, such as an alcohol or acetone,and/or a moisturizer such as glycerol or an oil such as castor oil orarachis oil.

Creams, ointments or pastes according to the present invention aresemi-solid formulations of the active ingredient for externalapplication. They may be made by mixing the active ingredient infinely-divided or powdered form, alone or in solution or suspension inan aqueous or non-aqueous fluid, with the aid of suitable machinery,with a greasy or non-greasy base. The base may comprise hydrocarbonssuch as hard, soft or liquid paraffin, glycerol, beeswax, a metallicsoap; a mucilage; an oil of natural origin such as almond, corn,arachis, castor or olive oil; wool fat or its derivatives or a fattyacid such as steric or oleic acid together with an alcohol such aspropylene glycol or a macrogel. The formulation may incorporate anysuitable surface active agent such as an anionic, cationic or non-ionicsurfactant such as a sorbitan esteror a polyoxyethylene derivativethereof. Suspending agents such as natural gums, cellulose derivativesor inorganic materials such as silicaceous silicas, and otheringredients such as lanolin, may also be included.

Drops according to the present invention may comprise sterile aqueous oroily solutions or suspensions and may be prepared by dissolving theactive ingredient in a suitable aqueous solution of a bactericidaland/or fungicidal agent and/or any other suitable preservative, andpreferably including a surface active agent. The resulting solution maythen be clarified by filtration, transferred to a suitable containerwhich is then sealed and sterilized by autoclaving or maintaining at98-100° C. for half an hour. Alternatively, the solution may besterilized by filtration and transferred to the container by an aseptictechnique. Examples of bactericidal and fungicidal agents suitable forinclusion in the drops are phenylmercuric nitrate or acetate (0.002%),benzalkonium chloride (0.01%) and chlorhexidine acetate (0.01%).Suitable solvents for the preparation of an oily solution includeglycerol, diluted alcohol and propylene glycol.

Compounds of formula (I) may be administered parenterally, that is byintravenous, intramuscular, subcutaneous intranasal, intrarectal,intravaginal or intraperitoneal administration. The subcutaneous andintramuscular forms of parenteral administration are generallypreferred. Appropriate dosage forms for such administration may beprepared by conventional techniques. Compounds of formula (I) may alsobe administered by inhalation, that is by intranasal and oral inhalationadministration. Appropriate dosage forms for such administration, suchas an aerosol formulation or a metered dose inhaler, may be prepared byconventional techniques.

For all methods of use disclosed herein for the compounds of formula(I), the daily oral dosage regimen will preferably be from about 0.1 toabout 80 mg/kg of total body weight, preferably from about 0.2 to 30mg/kg, more preferably from about 0.5 mg to 15 mg. The daily parenteraldosage regimen about 0.1 to about 80 mg/kg of total body weight,preferably from about 0.2 to about 30 mg/kg, and more preferably fromabout 0.5 mg to 15 mg/kg. The daily topical dosage regimen willpreferably be from 0.1 mg to 150 mg, administered one to four,preferably two or three times daily. The daily inhalation dosage regimenwill preferably be from about 0.01 mg/kg to about 1 mg/kg per day. Itwill also be recognized by one of skill in the art that the optimalquantity and spacing of individual dosages of a compound of formula (I)or a pharmaceutically acceptable salt thereof will be determined by thenature and extent of the condition being treated, the form, route andsite of administration, and the particular patient being treated, andthat such optimums can be determined by conventional techniques. It willalso be appreciated by one of skill in the art that the optimal courseof treatment, ie., the number of doses of a compound of formula (I) or apharmaceutically acceptable salt thereof given per day for a definednumber of days, can be ascertained by those skilled in the art usingconventional course of treatment determination tests.

The invention will now be described by reference to the followingexamples which are merely illustrative and are not to be construed as alimitation of the scope of the present invention.

Biological Examples

The cytokine-inhibiting effects of compounds of the present inventionare determined by the following in vitro assays:

Interleukin 1 (IL-1)

Human peripheral blood monocytes were isolated and purified from eitherfresh blood preparations from volunteer donors, or from blood bank buffycoats, according to the procedure of Colotta et al, J Immunol, 132,936(1984). These monocytes (1×10⁶) were plated in 24-well plates at aconcentration of 1-2 million/ml per well. The cells were allowed toadhere for 2 hours, after which time non-adherent cells were removed bygentle washing. Test compounds were then added to the cells for 1hbefore the addition of lipopolysaccharide (50 ng/ml), and the cultureswere incubated at 37° C. for an additional 24h. At the end of thisperiod, culture supernatants were removed and clarified of cells and alldebris. Culture supernatants were then immediately assayed for IL-1biological activity, either by the method of Simon et al., J. Immunol.Methods, 84, 85, (1985) (based on ability of IL-1 to stimulate aInterleukin 2 producing cell line (EL-4) to secrete IL-2, in concertwith A23187 ionophore) or the method of Lee et al., J. ImmunoTherapy, 6(1), 1-12 (1990) (ELISA assay). Compounds of formula (I) as illustratedby Examples 1, 2, and 7 herein were shown to be inhibitors of in vitroIL-1 produced by human monocytes.

Tumor Necrosis Factor (TNF)

Human peripheral blood monocytes are isolated and purified from eitherblood bank buffy coats or plateletpheresis residues, according to theprocedure of Colotta, R. et al., J Immunol, 132(2), 936 (1984). Themonocytes are plated at a density of 1×10⁶ cells/ml medium/well in24-well multi-dishes. The cells are allowed to adhere for 1 hour afterwhich time the supernatant is aspirated and fresh medium (1 ml,RPMI-1640, Whitaker Biomedical Products, Whitaker, Calif.) containing 1%fetal calf serum plus penicillin and streptomycin (10 units/ml) added.The cells are incubated for 45 minutes in the presence or absence of atest compound at 1 nM-10 mM dose ranges (compounds were solubilized indimethyl sulfoxide/ethanol, such that the final solvent concentration inthe culture medium is 0.5% dimethyl sulfoxide/0.5% ethanol). Bacteriallipopoly-saccharide (E. coli 055:B5 [LPS] from Sigma Chemicals Co.) isthen added (100 ng/ml in 10 ml phosphate buffered saline) and culturesincubated for 16-18 hours at 37° C. in a 5% CO₂ incubator. At the end ofthe incubation period, culture supernatants are removed from the cells,centrifuged at 3000 rpm to remove cell debris. The supernatant is thenassayed for TNF activity using either a radio-immuno or an ELISA assay,as described in WO 92/10190 and by Becker et al., J Immunol, 1991,147,4307.

Interleukin 8 (IL8)

Primary human umbilical cord endothelial cells (HUVEC) (Cell Systems,Kirland, Wash.) are maintained in culture medium supplemented with 15%fetal bovine serum and 1% CS-HBGF consisting of aFGF and heparin. Thecells are then diluted 20-fold before being plated (250 μl) intogelating coated 96-well plates. Prior to use, culture medium is replacedwith fresh medium (200 μl). Buffer or test compound (25 μl; atconcentrations between 1 and 10 μM) is then added to each well inquadruplicate wells and the plates incubated for 6h in a humidifiedincubator at 37° C. in an atmosphere of 5% CO₂. At the end of theincubation period, supernatant is removed and assayed for IL-8concentration using an IL-8 ELISA kit obtained from R&D Systems(Minneapolis, Minn.). All data is presented as mean value (ng/ml) ofmultiple samples based on the standard curve. IC_(50')s whereappropriate are generated by non-linear regression analysis.

Cytokine Specific Binding Protein Assay

A radiocompetitive binding assay was developed to provide a highlyreproducible primary screen for structure-activity studies. This assayprovides many advantages over the conventional bioassays which utilizefreshly isolated human monocytes as a source of cytokines and ELISAassays to quantify them. Besides being a much more facile assay, thebinding assay has been extensively validated to highly correlate withthe results of the bioassay. A specific and reproducible binding assaywas developed to test compounds belonging to the CSAID™ class ofcompounds using soluble cystosolic fraction from THP.1 cells and aradiolabeled compound. For instance, a suitable radiolabeled compound ofthe CSAID™ class of compounds is4-(Fluorophenyl)-2-(4-hydroxyphenyl-3,5-t₂)-5-(4-pyridyl)imidazole whichmay be made in an analagous procedures as demonstrated in Adams et al.,WO93/14081 or as illustrated below.

In brief, the THP.1 cytosol was routinely prepared from cell lysateobtained by nitrogen cavitation followed by a 10 K×g low speed and a 100K×g high speed centrifugation, the supernatant of which was designatedas the cytosolic fraction. THP.1 cytosol was incubated withappropriately diluted radioligand at room temperature for apre-determined time to allow the binding to achieve equilibrium. Thesample was added to a G-10 column and eluted with 20 mm TRN, 50mMb-mercaptoethanol, NaN₃. The fraction encompassing the void volume wascollected and the radioactivity was assessed by liquid scintillationcounting. This was determined to reflect bound radioligand since theradioactive signal was abrogated by the presence of excess cold ligandin the incubation mixture or when there was no cytosolic fractionpresent. Compounds of Formula (I) at various doses were added to thebinding assay to achieve inhibition of binding of the radiolabel. IC₅₀sas well as Ki values were determined by regression analysis andscatchard plot analysis respectively. There is generally excellentcorrelation between the IC₅₀ of compounds tested in both the bindingassay and the bioassay and can be used interchangeably in many cases.Compounds of Formula (I) as illustrated by Examples 1 to 14 herein wereshown to have activity in the CSBP assay.

Patent Application U.S. Ser. No. 08/123,175 Lee et al., filed September1993, whose disclosure is incorporated by reference herein in itsentirety also describes the above noted method for screening drugs toidentify compounds which interact with and bind to the CSBP. However,for purposes herein, the binding protein may be in isolated form insolution, or in immobilized form, or may be genetically engineered to beexpressed on the surface of recombinant host cells such as in phagedisplay system or as fusion proteins. Alternatively, whole cells orcytosolic fractions comprising the CSBP may be employed in the creeningprotocol. Regardless of the form of the binding protein, a plurality ofcompounds are contacted with the binding protein under conditionssufficient to form a compound/ binding protein complex and compoundcapable of forming, enhancing or interfering with said complexes aredetected.

More specifically, the Cytokine Specific Binding Assay is performed asfollows:

MATERIALS

Incubation buffer: 20 mM Tris, 1 mM MgCl₂, 20 mM Hepes, 0.02% NaN₃,store at 4° C. Elution buffer: 20 mM Tris, 50 mM 2-mercaptoethanol,NaN₃, store at 4° C.

G-10 Sephadex: add 100 g Sephadex G-10 (Pharmacia, Uppsala, Sweden) to400 mL dd H₂O and allow to swell at room temperature for 2 hours. Decantfines and wash 3 times. Add NaN₃ and qs with dd H₂O to 500 mLs and storeat 4° C.

Assemble Columns: Straw column, filter frit and tip (Kontes, SP420160-000, 420162-002). Lowsorb tubes (Nunc) used in binding reaction.THP.1 cytosol spun at 15000 rpm for 5 min to clarify. THP.1 cytosolprepared by hypnotic treatment of cells and lysis by decompression innitrogen. Nuclei and membrane fragments removed by differentialcentrifugation (10,000 g for 1 hour and 100,000 g for 1 hour).

Compounds: Non-radioactive Compound I with corresponding EtOH control(dilutions made in incubation buffer) and ³H-Compound I (dilutions inincubation buffer).

METHOD

A. Column Preparation

1) Begin 30 min before anticipated elution of reaction mixture; 2) Add 3mL of G-10 slurry to column for bed vol of 1.5 ml; 3) Rinse with 7 mLelution buffer (fill to top of column); 4) Cut columns down to size.

B. Sample Incubation

1) 15 min incubation at 4° C.; 2) Binding reaction mixture; 100 μLcytosol, 10 μL cold Compound I or EtOH control, 10 μL ³H-Compound I(molar concentration depends on nature of study); 3) “Free” control=100μL incubation buffer in lieu of cytosol preparation.

C. Sample Elution

1) Elute at 4° C.; 2) Add total reaction volume to G-10 column; 3) Add400 μL elution buffer to column and discard eluate; 4) Add 500 μLelution buffer to column, collecting eluted volume in 20 mlscintillation vial; 5) Add 15 mL Ready Safe scintillation fluid; 6)Vortex and count in liquid scintillation counter for 5 minutes. Includea “total input counts control” (10 μL of labeled ligand).

D. Data Analysis

1) Plot DPMS as output in graphic form and analyze by regressionanalysis and “Lundon ligand binding” software for the determination ofIC 50 and Kd/Ki respectively; 2) Rank order the IC50s of the testedcompounds in the CSAIDbioassay and compare to that generated by theCSAID binding assay and establish a correlation curve.

The binding assay was further validated by the following criteria, i.e.THP.1 cytosol demonstrated saturable and specific binding of theradiolabeled compound.

Preparation of4-(Fluorophenyl)-2-(4-hydroxyphenyl-3,5-t₂)-5-(4-pyridyl)imidazole,(Compound I)

A 2.9 mg (0.0059 mmol) portion of2-(3,5-Dibromo-4-hydroxyphenyl)-4-(4-fluorophenyl)-5-(4-pyridyl)imidazole,Compound I, was dissolved in 0.95 mL of dry DMF and 0.05 mL oftriethylamine in a 2.4 mL round bottom flask equipped with a smallmagnetic stirring bar. A 1.7 mg portion of 5% Pd/C (Engelhard lot 28845)was added, and the flask was attached to the stainless steel tritiummanifold. The mixture was degassed through four freeze-pump-thaw cycles,then tritium gas (5.3 Ci, 0.091 mmol) was introduced. The reactionmixture was allowed to warm to room temperature and was stirredvigorously for 20h. The mixture was frozen in liquid nitrogen, theremaining tritium gas (2.4 Ci) was removed, and the flask was removedfrom the manifold. The reaction mixture was transferred, using 3×1 mL ofmethanol as rinsings, into a 10 mL round bottom flask, and the solventswere removed by static vacuum transfer. A 1.5 mL portion of methanol wasadded to the residue, then removed by static vacuum transfer. The latterprocess was repeated. Finally, the residue was suspended in 1.5 mL ofethanol and filtered through a syringe-tip Millipore filter (0.45micron), along with 3×ca. 1 mL ethanol rinsings. The total filtratevolume was determined to be 3.9 mL, and the total radioactivity, 94.2mCi. Solution was determined to be 3.9 mL, and the total radioactivity,94.2 mCi. HPLC analysis of filtrate (Partisil 5 ODS-3, 4.6 mm I.D.×25cm, 1 mL/min of 70:30:01 water/acetonitrile/trifluoroacetic acid,Radiomatic Flo-One Beta radio detector with 3 mL/min of Ecoscint-Hcocktail through a 0.75 mL cell) showed the presence of Compound I(R_(t)=60 min. ca. 37% of total radioactivity), and a discreteintermediate presumed to be the monobromo derivative Compound Ia(R_(t)=11.8 min, ca. 9%).

The filtrate solution was evaporated to near dryness with a stream ofnitrogen, and the residue was dissolved in about 1.2 mL of the HPLCmobile phase. The solution was separated by HPLC as shown below, and thepeaks corresponding to Compounds I and Ia and SB collected separately.

HPLC Method Column Altex Ultrasphere 10 mm I.D. × 25 cm Mobile Phase70:30:0.1 water/acetonitrile/trifluoroacetic acid Flow Rate 5 mL/min UVdetection 210 nm Injection Volumes 0.05-0.4 m: Retention Times 7.8 minCompound I 24 min Compound Ia

The pooled Compound I fractions totaled 32 mL in volume and theradioactive concentration was 1.52 mCi/mL (total 48.6 m Ci). The pooledSB Compound Ia [³H] fractions (totaling 10.1 mCi) were evaporated todryness and the residue was transferred quantitatively into a glass vialusing 3.8 mL of absolute ethanol for further analysis.

An 8 mL (12.2 mCi) portion of Compound I was evaporated to dryness invacuo at <35° C., then redissolved in 0.5 mL of mobile phase. The wholevolume was injected into the HPLC system described above, and theappropriate peak was collected. Evaporation of the collected eluate invacuo at <35° C. and transfer of the yellow residue into a vial withabsolute ethanol provided a solution (3.8 mL, 2.44 mCi/mL) of CompoundI. The portion of this solution used for NMR analyses was firstevaporated to dryness using stream of nitrogen then taken up in CD₃OD.

Analysis of4-(4-Fluorophenyl)-2-(4-hydroxyphenyl-3,5-t₂)-5-(4-pyridyl)imidazole,Compound I.

Radiochemical Purity by HPLC Method Column Ultrasphere Octyl, 5 mm, 4.6mm I.D. × 25 cm, Beckman Mobile Phase 350:150:0.5 (v/v/v)water/acetonitrile/trifluoroacetic acid Flow Rate 1.0 mL/min Massdetection UV at 210 nm Radioactivity detection Ramona-D radioactivityflow detector Scintillator Tru-Count Tru-Lab Supply Co.) Flow rate 5.0mL/min Cell volume 0.75 mL Retention time 7.7 min Result 98.7Radioactive Concentration by Scintillation Counting Method ScintillatorReady Safe (Beckman Instruments, Inc.) Instrument TM Analytic model 6881Efficiency Automated DPM calculation from quench curve Result 2.44mCi/mL Specific Activity by Mass Spectrometry Method CI-MS, NH₃ reagentgas Result 20.0 Ci/mmol ³H Distribution: Unlabeled 44% Single Label 43%Double Label 13% ³H NMR⁹ Method Instrument Brunker AM 400 ExperimentProton decoupled ³H NMR Proton non-decoupled ³H NMR Proton non-decoupled³H NMR Peak Referencing Solvent Peak: of methanol ∂ 3.3 SolventMethanol-d₄ Result Tritium is incorporated exclusively on the carbonatoms ortho to aromatic hydroxyl group Analytical Summary Assay ResultRadiochemical purity determined by HPLC 98.7% Radioactivityconcentration determined by 2.44 mCi/mL scintillation counting Specificactivity determined by mass spectrometry 20.0 Ci/mmol ³H NMR agrees withthe proposed structure

The above description fully discloses the invention including preferredembodiments thereof. Modifications and improvements of the embodimentsspecifically disclosed herein are within the scope of the followingclaims. Without further elaboration, it is believed that one skilled inthe art can, using the preceding description, utilize the presentinvention to its fullest extent. Therefore the Examples herein are to beconstrued as merely illustrative and not a limitation of the scope ofthe present invention in any way. The embodiments of the invention inwhich an exclusive property or privilege is claimed are defined asfollows.

What is claimed is:
 1. A compound of the formula:

wherein: one of R₁ or R₂ is an optionally substituted aryl ring and theother of R₁ or R₂ is an optionally substituted 4-pyridyl ring; whereinwhen one of R₁ and R₂ is an optionally substituted aryl ring, the ringis substituted by one or two substituents, each of which isindependently selected from a group consisting of a 4-phenyl,4-naphth-1-yl or 5-naphth-2-yl substituent, is halo, cyano, C(Z)NR₇R₁₇,C(Z)OR₂₃, (CR₁₀R₂₀)_(m)COR₃₆, SR₅, SOR₅, OR₃₆, halo-substituted-C₁₋₄alkyl, C₁₋₄ alkyl, ZC(Z)R₃₆, NR₁₀C(Z)R₂₃, and (CR₁₀R₂₀)_(m)NR₁₀R₂₀; andother positions of substitution, is halo, (CR₁₀R₂₀)_(m″−)-cyano,C(Z)NR₁₆R₂₆, C(Z)OR₈, (CR₁₀R₂₀)_(m″)COR₈, (CR₁₀R₂₀)_(m″)S(O)_(m)R₈,(CR₁₀R₂₀)_(m″)OR₈, halo-substituted-C₁₋₄ alkyl, C₁₋₄ alkyl,(CR₁₀R₂₀)_(m″)NR₁₀C(Z)R₈, (CR₁₀R₂₀)_(m″)NR₁₀S(O)_(m′)R₁₁,(CR₁₀R₂₀)_(m″)NR₁₀S(O)_(m′—)-NR₇R₁₇, (CR₁₀R₂₀)_(m″)ZC(Z)R₈ and(CR₁₀R₂₀)_(m″)NR₁₆R₂₆; and when one of R₁ and R₂ is the optionallysubstituted 4-pyridyl ring, the said ring is substituted by one or twosubstituents each of which is independently selected from C₁₋₄ alkyl,halo, C₁₋₄ alkoxy, C₁₋₄ alkylthio, NR₁₀R₂₀, or an N-heterocyclyl ringwhich ring has from 5 to 7 members and optionally contains an additionalheteroatom selected from oxygen, sulfur and NR₂₂; R₃ is hydrogen,(CR₁₀R₂₀)_(n)(Y₂)_(p), or halosubstituted C₁₋₁₀ alkyl; t is an integerhaving a value of 1 to 3; p is 0 or an integer having a value of 1,provided that when p is 0 then Y₂ is hydrogen; Z is oxygen or sulfur; nis 0 or an integer having a value of 1 to 10; n′ is an integer having avalue of 1 to 10; m is 0, or the integer 1 or 2; m′ is 1 or 2; m″ is 0or an integer having a value of 1 to 5; Y₂ is halogen, OR₈, NO₂,S(O)_(m′)R₁₁, SR₈, S(O)_(m′)NR₈R₉, NR₈R₉, O(CR₁₀R₂₀)_(n′)NR₈R₉, C(O)R₈,CO₂R₈, CO₂(CR₁₀R₂₀)_(n′)CONR₈R₉, ZC(O)R₈, CN, C(Z)NR₈R₉, NR₁₀C(Z)R₈,C(Z)NR₈OR₉, NR₁₀C(Z)NR₈R₉, NR₁₀S(O)_(m′)R₁₁, N(OR₂₁)C(Z)NR₈R₉,N(OR₂₁)C(Z)R₈, C(═NOR₂₁)R₈, NR₁₀C(═NR₁₅)SR₁₁, NR₁₀C(═NR₁₅)NR₈R₉,NR₁₀C(═CR₁₄R₂₄)SR₁₁, NR₁₀C(═CR₁₄R₂₄)NR₈R₉, NR₁₀C(O)C(O)NR₈R₉,NR₁₀C(O)C(O)OR₁₀, C(═NR₁₃)NR₈R₉, C(═NOR₁₃)NR₈R₉, C(═NR₁₃)ZR₁₁,OC(Z)NR₈R₉, NR₁₀S(O)₂CF₃, NR₁₀C(Z)OR₁₀, 5-(R₁₈)-1,2,4-oxadizaol-3-yl or4-(R₁₂)-5-(R₁₈R₁₉)-4,5-dihydro-1,2,4-oxadiazol-3-yl; provided that whenY₂ is CO₂R₈ or C(Z)NR₈R₉, then n is 0; R₅ is hydrogen, C₁₋₄ alkyl, C₂₋₄alkenyl, C₂₋₄ alkynyl or NR₇R₁₇, with the provisio that —SR₅ is not—SNR₇R₁₇ and —SOR₅ is not —SOH; R₆ is C₁₋₄ alkyl, halo-substituted-C₁₋₄alkyl, C₂₋₄ alkenyl, C₂₋₄ alkynyl or C₃₋₅ cycloalkyl; R₇ and R₁₇ is eachindependently selected from hydrogen or C₁₋₄ alkyl or R₇ and R₁₇together with the nitrogen to which they are attached form aheterocyclic ring of 5 to 7 members which ring optionally contains anadditional heteroatom selected from oxygen, sulfur or NR₂₂; R₈ ishydrogen, heterocyclyl, heterocyclylalkyl or R₁₁; R₉ is hydrogen, C₁₋₁₀alkyl, C₂₋₁₀ alkenyl, C₂₋₁₀ alkynyl, C₃₋₇ cycloalkyl, C₅₋₇ cycloalkenyl,aryl, arylalkyl, heteroaryl or heteroarylalkyl or R₈ and R₉ may togetherwith the nitrogen to which they are attached form a heterocyclic ring of5 to 7 members which ring optionally contains an additional heteroatomselected from oxygen, sulfur or NR₁₂; R₁₀ and R₂₀ is each independentlyselected from hydrogen or C₁₋₄ alkyl; R₁₁ is C₁₋₁₀ alkyl,halo-substituted C₁₋₁₀ alkyl, C₂₋₁₀ alkenyl, C₂₋₁₀ alkynyl, C₃₋₇cycloalkyl, C₅₋₇ cycloalkenyl, aryl, arylalkyl, heteroaryl orheteroarylalkyl; R₁₂ is hydrogen, —C(Z)R₁₃ or optionally substitutedC₁₋₄ alkyl, optionally substituted aryl or optionally substitutedaryl-C₁₋₄ alkyl; R₁₃ is hydrogen, C₁₋₁₀ alkyl, cycloalkyl, heterocyclyl,aryl, arylalkyl, heteroaryl or heteroarylalkyl; R₁₄ and R₂₄ is eachindependently selected from hydrogen, alkyl, nitro or cyano; R₁₅ ishydrogen, cyano, C₁₋₄ alkyl, C₃₋₇ cycloalkyl or aryl; R₁₆ and R₂₆ iseach independently selected from hydrogen or optionally substituted C₁₋₄alkyl, optionally substituted aryl or optionally substituted aryl-C₁₋₄alkyl, or together with the nitrogen which they are attached form aheterocyclic ring of 5 to 7 members which ring optionally contains anadditional heteroatom selected from oxygen, sulfur or NR₁₂; R₁₈ and R₁₉is each independently selected from hydrogen, C₁₋₄ alkyl, substitutedalkyl, optionally substituted aryl, optionally substituted arylalkyl ortogether R₁₈ and R₁₉ denote a oxygen or sulfur; R₂₁ is hydrogen, apharmaceutically acceptable cation, C₁₋₁₀ alkyl, C₃₋₇ cycloalkyl, aryl,aryl C₁₋₄ alkyl, heteroaryl, heteroarylalkyl, heterocyclyl, aroyl, orC₁₋₁₀ alkanoyl; R₂₂ is R₁₀ or C(Z)—C₁₋₄ alkyl; R₂₃ is C₁₋₄ alkyl,halo-substituted-C₁₋₄ alkyl, or C₃₋₅ cycloalkyl; R₃₆ is hydrogen or R₂₃;or a pharmaceutically acceptable salt thereof.
 2. The compound accordingto claim 1 wherein R₁ or R₂ is a substituted 4-pyridyl.
 3. The compoundaccording to claim 1 wherein the substituent is C₁₋₄ alkyl or NR₁₀R₂₀.4. The compound according to claim 1 wherein R₁ or R₂ is an optionallysubstituted phenyl.
 5. The compound according to claim 4 wherein one ormore of the optional substituents are independently selected fromhalogen or methoxy.
 6. The compound according to claim 1 wherein R₃ ishydrogen, (CR₁₀R₂₀)_(n)(Y₂)_(p), or (CR₁₀R₂₀)_(n)CH₃; and Y₂ is —NR₈R₉or —NR₁₀C(Z)R₈.
 7. The compound according to claim 5 wherein R₃ ishydrogen, methyl, amino, or —NR₁₀C(O)R₈.
 8. The compound according toclaim 1 which is: 5-(3-Methoxyphenyl)-2-methyl-4-(4-pyridyl)oxazole;5-(4-Fluorophenyl)-2-methyl-4-(4-pyridyl)oxazole;2-Methyl-4-(Phenyl)-5-(4-pyridyl)oxazole;4-(4-Fluorophenyl)-2-methyl-5-(4-pyridyl)oxazole;2-Amino-4-(4-fluorophenyl)-5-(4-pyridyl)oxazole;4-(4-Fluorophenyl)-5-(4-pyridyl)oxazole;4-(4-Fluorophenyl)-5-(2-methylpyrid-4-yl)oxazole;4-(3,4-Dichlorophenyl)-5-(4-pyridyl)oxazole;4-(3-Chlorophenyl)-5-(4-pyridyl)oxazole;2-Acetamido-4-(4-fluorophenyl)-5-(4-pyridyl)oxazole; or apharmaceutically acceptable salt thereof.
 9. A pharmaceuticalcomposition comprising a pharmaceutically acceptable carrier or diluentand a compound according to claim
 1. 10. A method of treating a cytokinemediated disease in an animal in need thereof which method comprisesadministering to said animal an effective cytokine mediating amount of acompound according to claim
 1. 11. The method according to claim 10wherein the cytokine mediated disease is asthma, adult respiratorydistress syndrome, stroke, bone reasorption diseases, or arthritic jointconditions.
 12. The method according to claim 10 wherein the compound is5-(3-Methoxyphenyl)-2-methyl-4-(4-pyridyl)oxazole;5-(4-Fluorophenyl)-2-methyl-4-(4-pyridyl)oxazole;2-Methyl-4-(Phenyl)-5-(4-pyridyl)oxazole;4-(4-Fluorophenyl)-2-methyl-5-(4-pyridyl)oxazole;2-Amino-4-(4-fluorophenyl)-5-(4-pyridyl)oxazole;4-(4-Fluorophenyl)-5-(4-pyridyl)oxazole;4-(4-Fluorophenyl)-5-(2-methylpyrid-4-yl)oxazole;4-(3,4-Dichlorophenyl)-5-(4-pyridyl)oxazole;4-(3-Chlorophenyl)-5-(4-pyridyl)oxazole;2-Acetamido-4-(4-fluorophenyl)-5-(4-pyridyl)oxazole; or apharmaceutically acceptable salt thereof.
 13. The method according toclaim 11 wherein the mediation of the disease state is by Interleukin-1(IL-1).
 14. The method according to claim 11 wherein the mediation ofthe disease state is by Tumor Necrosis Factor (TNF).
 15. A method oftreating inflammation in a mammal in need thereof which comprisesadministering to said mammal an effective amount of a compound accordingto claim
 1. 16. The method according to claim 11 wherein the cytokinemediated disease is arthritis, rheumatoid arthritis, rheumatoidspondylitis, osteoarthritis, traumatic arthritis, rubella arthritis,acute synovitis, gouty arthritis, gout, sepsis, septic shock, endotoxicshock, gram negative sepsis, toxic shock syndrome, diabetes,atherosclerosis, adult respiratory distress syndrome, cerebral malaria,chronic pulmonary inflammatory disease, silicosis, pulmonarysarcoisosis, bone resorption diseases, reperfusion injury, thrombosis,glomerulonepthritis, stroke, graft vs. host reaction, allograftrejections, fever and myalgias due to infection, cachexia secondary toinfection or malignancy, cachexia secondary to acquired immunedeficiency syndrome, keloid formation, scar tissue formation, eczema,psoriasis, Crohn's disease, inflammatory bowel disease, ulcerativecolitis or pyresis.